c语言中怎么用string函数提取字符串

?C???,????string.h????????????????

1. ??strncpy??:

#include 
#include 

int main() {
    char source[] = "Hello, World!";
    char destination[20];
    int n = 5; // ??????

    strncpy(destination, source, n);
    destination[n] = '\0';

    printf("???????:%s\n", destination);

    return 0;
}

2. ??sscanf??:

#include 

int main() {
    char source[] = "Hello, World!";
    char destination[20];

    sscanf(source, " s", destination);

    printf("???????:%s\n", destination);

    return 0;
}

3. ??strtok??:

#include 
#include 

int main() {
    char source[] = "Hello, World!";
    char *token;

    token = strtok(source, " "); // ???????

    while (token != NULL) {
        printf("???????:%s\n", token);
        token = strtok(NULL, " "); // ??????????
    }

    return 0;
}

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