Dette emnet vil diskutere hvordan vi kan dele opp gitte strenger i ett enkelt ord i C++ programmeringsspråk . Når vi deler en gruppe ord eller strengsamlinger i enkeltord, kalles det dele eller deling av strengen. Imidlertid er det bare mulig å dele strenger med noen skilletegn som mellomrom ( ), komma (,), en bindestrek (-) osv., noe som gjør ordene til et individ. Videre er det ingen forhåndsdefinert delt funksjon for å dele opp samlingen av strenger i en individuell streng. Så her vil vi lære de forskjellige metodene for å dele strenger til en enkelt i C++.

Annen metode for å oppnå splitting av strenger i C++

1. Bruk strtok()-funksjonen for å dele strenger
2. Bruk egendefinert split() funksjon for å dele strenger
3. Bruk funksjonen std::getline() for å dele en streng
4. Bruk funksjonen find() og substr() for å dele en streng

Bruk strtok()-funksjonen for å dele strenger

strtok(): En strtok()-funksjon brukes til å dele den opprinnelige strengen i biter eller tokens basert på skilletegnet som er bestått.

Syntaks

 char *ptr = strtok( str, delim) 

I syntaksen ovenfor har en strtok() to parametere, den str , og jeg deler .

str : En str er en original streng som strtok() funksjonen delte strenger fra.

jeg deler : Det er et tegn som brukes til å dele en streng. For eksempel komma (,), mellomrom ( ), bindestrek (-) osv.

Komme tilbake : Den returnerer en peker som refererer til neste tegnsymboler. Til å begynne med peker den på strengenes første token.

Merk: En strtok()-funksjon endrer den opprinnelige strengen og setter et NULL-tegn ('') på skilletegnposisjonen på hvert kall til strtok()-funksjonen. På denne måten kan den enkelt spore statusen til tokenet.

Program for å dele strenger ved å bruke strtok()-funksjonen

La oss vurdere et eksempel for å dele en streng i C++ ved å bruke strtok()-funksjonen.

Program.cpp

 #include #include using namespace std; int main() { char str[100]; // declare the size of string cout &lt;&lt; &apos; Enter a string: &apos; &lt;<endl; cin.getline(str, 100); use getline() function to read a string from input stream char *ptr; declare ptr pointer ' , '); strtok() separate using comma (,) delimiter. cout << 
 split function: endl; while loop check is not null (ptr !="NULL)" { print the token (null, } return 0; < pre> <p> <strong>Output</strong> </p> <pre> Enter a string: Learn how to split a string in C++ using the strtok() function. Split string using strtok() function: Learn how to split a string in C++ Using the strtok() function. </pre> <h3>Program to use custom split() function to split strings</h3> <p>Let&apos;s write a program to split sequences of strings in C++ using a custom split() function.</p> <p> <strong>Program2.cpp</strong> </p> <pre> #include #include #define max 8 // define the max string using namespace std; string strings[max]; // define max string // length of the string int len(string str) { int length = 0; for (int i = 0; str[i] != &apos;&apos;; i++) { length++; } return length; } // create custom split() function void split (string str, char seperator) { int currIndex = 0, i = 0; int startIndex = 0, endIndex = 0; while (i <= len(str)) { if (str[i]="=" seperator || i="=" endindex="i;" string substr ; substr.append(str, startindex, - startindex); strings[currindex]="subStr;" currindex +="1;" startindex="endIndex" 1; } i++; int main() str="Program to split strings using custom split function." char space split(str, seperator); cout <<' the split is: '; for (int < max; i++) << '
 : ' strings[i]; return 0; pre> <p> <strong>Output</strong> </p> <pre> The split string is: i : 0 Program i : 1 to i : 2 split i : 3 strings i : 4 using i : 5 custom i : 6 split i : 7 function. </pre> <h3>Use std::getline() function to split string</h3> <p>A getline() function is a standard library function of C++ used to read the string from an input stream and put them into the vector string until delimiter characters are found. We can use <strong>std::getline()</strong> function by importing the header file.</p> <p> <strong>Syntax</strong> </p> <pre> getline(str, token, delim); </pre> <p>It has three parameters:</p> <p> <strong>str:</strong> A str is a variable that stores original string.</p> <p> <strong>token:</strong> It stores the string tokens extracted from original string.</p> <p> <strong>delim:</strong> It is a character that are used to split the string. For example, comma (,), space ( ), hyphen (-), etc.</p> <h3>Program to use getline() function to split strings</h3> <p>Let&apos;s consider an example to split strings using the getline() function in C++.</p> <p> <strong>Program3.cpp</strong> </p> <pre> #include #include #include #include using namespace std; int main() { string S, T; // declare string variables getline(cin, S); // use getline() function to read a line of string and store into S variable. stringstream X(S); // X is an object of stringstream that references the S string // use while loop to check the getline() function condition while (getline(X, T, &apos; &apos;)) { /* X represents to read the string from stringstream, T use for store the token string and, &apos; &apos; whitespace represents to split the string where whitespace is found. */ cout &lt;&lt; T &lt;&lt; endl; // print split string } return 0; } </pre> <p> <strong>Output</strong> </p> <pre> Welcome to the JavaTpoint and Learn C++ Programming Language. Welcome to the JavaTpoint and Learn C++ Programming Language. </pre> <h3>Program to split the given string using the getline() function</h3> <p>Let&apos;s consider an example to split a given string in C++ using the getline() function.</p> <p> <strong>Program4.cpp</strong> </p> <pre> #include #include #include #include void split_str( std::string const &amp;str, const char delim, std::vector &amp;out ) { // create a stream from the string std::stringstream s(str); std::string s2; while (std:: getline (s, s2, delim) ) { out.push_back(s2); // store the string in s2 } } int main() { std:: string s2 = &apos;Learn How to split a string in C++&apos;; const char delim = &apos; &apos;; /* define the delimiter like space (&apos; &apos;), comma (,), hyphen (-), etc. */ std::cout &lt;&lt; &apos;Your given string is: &apos; &lt;&lt; s2; std::vector out; // store the string in vector split_str (s2, delim, out); // call function to split the string // use range based for loop for (const auto &amp;s2: out) { std::cout &lt;&lt; &apos;
&apos; &lt;&lt; s2; } return 0; } </pre> <p> <strong>Output</strong> </p> <pre> Your given string is: Learn How to split a string in C++ Learn How to split a string in C++ </pre> <h3>Use find() and substr() function to split strings</h3> <p>Let&apos;s write a program to use find() function and substr() function to split given strings in C++.</p> <p> <strong>Program4.cpp</strong> </p> <pre> #include #include using namespace std; int main() { // given string with delimiter string given_str = &apos;How_to_split_a_string_using_find()_and_substr()_function_in_C++&apos;; string delim = &apos;_&apos;; // delimiter cout &lt;&lt; &apos; Your string with delimiter is: &apos; &lt;&lt; given_str &lt;&lt; endl; size_t pos = 0; string token1; // define a string variable // use find() function to get the position of the delimiters while (( pos = given_str.find (delim)) != std::string::npos) { token1 = given_str.substr(0, pos); // store the substring cout &lt;&lt; token1 &lt;&lt; endl; given_str.erase(0, pos + delim.length()); /* erase() function store the current positon and move to next token. */ } cout &lt;&lt; given_str &lt;&lt; endl; // it print last token of the string. } </pre> <p> <strong>Output</strong> </p> <pre> Your string with delimiter is: How_to_split_a_string_using_find()_and_substr()_function_in_C++ How to split a string using find() and substr() function in C++ </pre> <p>In the above program, we use a <strong>find()</strong> function inside the loop to repeatedly find the occurrence of the delimiter in the given string and then split it into tokens when the delimiter occurs. And the <strong>substr()</strong> function stores the sub-string to be printed. On the other hand, an erase() function stores the current position of the string and moves to the next token, and this process continues until we have got all the split strings.</p> <hr></=></pre></endl;>

Program for å bruke egendefinert split() funksjon for å dele strenger

La oss skrive et program for å dele sekvenser av strenger i C++ ved å bruke en egendefinert split()-funksjon.

Program2.cpp

mysql vis alle brukere

 #include #include #define max 8 // define the max string using namespace std; string strings[max]; // define max string // length of the string int len(string str) { int length = 0; for (int i = 0; str[i] != &apos;&apos;; i++) { length++; } return length; } // create custom split() function void split (string str, char seperator) { int currIndex = 0, i = 0; int startIndex = 0, endIndex = 0; while (i <= len(str)) { if (str[i]="=" seperator || i="=" endindex="i;" string substr ; substr.append(str, startindex, - startindex); strings[currindex]="subStr;" currindex +="1;" startindex="endIndex" 1; } i++; int main() str="Program to split strings using custom split function." char space split(str, seperator); cout <<\' the split is: \'; for (int < max; i++) << \'
 : \' strings[i]; return 0; pre> <p> <strong>Output</strong> </p> <pre> The split string is: i : 0 Program i : 1 to i : 2 split i : 3 strings i : 4 using i : 5 custom i : 6 split i : 7 function. </pre> <h3>Use std::getline() function to split string</h3> <p>A getline() function is a standard library function of C++ used to read the string from an input stream and put them into the vector string until delimiter characters are found. We can use <strong>std::getline()</strong> function by importing the header file.</p> <p> <strong>Syntax</strong> </p> <pre> getline(str, token, delim); </pre> <p>It has three parameters:</p> <p> <strong>str:</strong> A str is a variable that stores original string.</p> <p> <strong>token:</strong> It stores the string tokens extracted from original string.</p> <p> <strong>delim:</strong> It is a character that are used to split the string. For example, comma (,), space ( ), hyphen (-), etc.</p> <h3>Program to use getline() function to split strings</h3> <p>Let&apos;s consider an example to split strings using the getline() function in C++.</p> <p> <strong>Program3.cpp</strong> </p> <pre> #include #include #include #include using namespace std; int main() { string S, T; // declare string variables getline(cin, S); // use getline() function to read a line of string and store into S variable. stringstream X(S); // X is an object of stringstream that references the S string // use while loop to check the getline() function condition while (getline(X, T, &apos; &apos;)) { /* X represents to read the string from stringstream, T use for store the token string and, &apos; &apos; whitespace represents to split the string where whitespace is found. */ cout &lt;&lt; T &lt;&lt; endl; // print split string } return 0; } </pre> <p> <strong>Output</strong> </p> <pre> Welcome to the JavaTpoint and Learn C++ Programming Language. Welcome to the JavaTpoint and Learn C++ Programming Language. </pre> <h3>Program to split the given string using the getline() function</h3> <p>Let&apos;s consider an example to split a given string in C++ using the getline() function.</p> <p> <strong>Program4.cpp</strong> </p> <pre> #include #include #include #include void split_str( std::string const &amp;str, const char delim, std::vector &amp;out ) { // create a stream from the string std::stringstream s(str); std::string s2; while (std:: getline (s, s2, delim) ) { out.push_back(s2); // store the string in s2 } } int main() { std:: string s2 = &apos;Learn How to split a string in C++&apos;; const char delim = &apos; &apos;; /* define the delimiter like space (&apos; &apos;), comma (,), hyphen (-), etc. */ std::cout &lt;&lt; &apos;Your given string is: &apos; &lt;&lt; s2; std::vector out; // store the string in vector split_str (s2, delim, out); // call function to split the string // use range based for loop for (const auto &amp;s2: out) { std::cout &lt;&lt; &apos;
&apos; &lt;&lt; s2; } return 0; } </pre> <p> <strong>Output</strong> </p> <pre> Your given string is: Learn How to split a string in C++ Learn How to split a string in C++ </pre> <h3>Use find() and substr() function to split strings</h3> <p>Let&apos;s write a program to use find() function and substr() function to split given strings in C++.</p> <p> <strong>Program4.cpp</strong> </p> <pre> #include #include using namespace std; int main() { // given string with delimiter string given_str = &apos;How_to_split_a_string_using_find()_and_substr()_function_in_C++&apos;; string delim = &apos;_&apos;; // delimiter cout &lt;&lt; &apos; Your string with delimiter is: &apos; &lt;&lt; given_str &lt;&lt; endl; size_t pos = 0; string token1; // define a string variable // use find() function to get the position of the delimiters while (( pos = given_str.find (delim)) != std::string::npos) { token1 = given_str.substr(0, pos); // store the substring cout &lt;&lt; token1 &lt;&lt; endl; given_str.erase(0, pos + delim.length()); /* erase() function store the current positon and move to next token. */ } cout &lt;&lt; given_str &lt;&lt; endl; // it print last token of the string. } </pre> <p> <strong>Output</strong> </p> <pre> Your string with delimiter is: How_to_split_a_string_using_find()_and_substr()_function_in_C++ How to split a string using find() and substr() function in C++ </pre> <p>In the above program, we use a <strong>find()</strong> function inside the loop to repeatedly find the occurrence of the delimiter in the given string and then split it into tokens when the delimiter occurs. And the <strong>substr()</strong> function stores the sub-string to be printed. On the other hand, an erase() function stores the current position of the string and moves to the next token, and this process continues until we have got all the split strings.</p> <hr></=>

Bruk funksjonen std::getline() for å dele en streng

En getline()-funksjon er en standard bibliotekfunksjon til C++ som brukes til å lese strengen fra en inngangsstrøm og legge dem inn i vektorstrengen til skilletegn blir funnet. Vi kan bruke std::getline() funksjon ved å importere overskriftsfilen.

Syntaks

 getline(str, token, delim); 

Den har tre parametere:

str: En str er en variabel som lagrer den opprinnelige strengen.

token: Den lagrer strengen som er hentet fra den originale strengen.

dele: Det er et tegn som brukes til å dele strengen. For eksempel komma (,), mellomrom ( ), bindestrek (-) osv.

Program for å bruke getline()-funksjonen til å dele strenger

La oss vurdere et eksempel for å dele strenger ved å bruke getline()-funksjonen i C++.

Program3.cpp

 #include #include #include #include using namespace std; int main() { string S, T; // declare string variables getline(cin, S); // use getline() function to read a line of string and store into S variable. stringstream X(S); // X is an object of stringstream that references the S string // use while loop to check the getline() function condition while (getline(X, T, ' ')) { /* X represents to read the string from stringstream, T use for store the token string and, ' ' whitespace represents to split the string where whitespace is found. */ cout << T << endl; // print split string } return 0; } 

Produksjon

 Welcome to the JavaTpoint and Learn C++ Programming Language. Welcome to the JavaTpoint and Learn C++ Programming Language. 

Program for å dele den gitte strengen ved å bruke getline()-funksjonen

La oss vurdere et eksempel for å dele en gitt streng i C++ ved å bruke getline()-funksjonen.

Program4.cpp

 #include #include #include #include void split_str( std::string const &str, const char delim, std::vector &out ) { // create a stream from the string std::stringstream s(str); std::string s2; while (std:: getline (s, s2, delim) ) { out.push_back(s2); // store the string in s2 } } int main() { std:: string s2 = 'Learn How to split a string in C++'; const char delim = ' '; /* define the delimiter like space (' '), comma (,), hyphen (-), etc. */ std::cout << 'Your given string is: ' << s2; std::vector out; // store the string in vector split_str (s2, delim, out); // call function to split the string // use range based for loop for (const auto &s2: out) { std::cout << '
' << s2; } return 0; } 

Produksjon

 Your given string is: Learn How to split a string in C++ Learn How to split a string in C++ 

Bruk funksjonen find() og substr() for å dele strenger

La oss skrive et program for å bruke fun()-funksjonen og substr()-funksjonen for å dele opp gitte strenger i C++.

Program4.cpp

 #include #include using namespace std; int main() { // given string with delimiter string given_str = 'How_to_split_a_string_using_find()_and_substr()_function_in_C++'; string delim = '_'; // delimiter cout << ' Your string with delimiter is: ' << given_str << endl; size_t pos = 0; string token1; // define a string variable // use find() function to get the position of the delimiters while (( pos = given_str.find (delim)) != std::string::npos) { token1 = given_str.substr(0, pos); // store the substring cout << token1 << endl; given_str.erase(0, pos + delim.length()); /* erase() function store the current positon and move to next token. */ } cout << given_str << endl; // it print last token of the string. } 

Produksjon

sdlc

 Your string with delimiter is: How_to_split_a_string_using_find()_and_substr()_function_in_C++ How to split a string using find() and substr() function in C++ 

I programmet ovenfor bruker vi en finne() funksjon inne i loopen for å gjentatte ganger finne forekomsten av skilletegnet i den gitte strengen og deretter dele det opp i tokens når skilletegnet oppstår. Og substr() funksjonen lagrer understrengen som skal skrives ut. På den annen side lagrer en erase()-funksjon gjeldende posisjon til strengen og flytter til neste token, og denne prosessen fortsetter til vi har fått alle de delte strengene.