WY c語言進階

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1）字串函數strlen的實現

#include <stdio.h>#include <string.h>size_t mylen(const char* s){    int cnt = 0;    int idx = 0;    while (s[idx] != ‘\0‘ ){        idx++;        cnt++;    }    return cnt;}int main(int argc, char const *argv[]){    char line[] = "HELLO";    printf("strlen=%lu\n", mylen(line));        return 0;    }

2）strcpy 函數實現

char* mycpy(char* dst, const char* src){    char* ret = dst;    while(*src != ‘\0‘){        *dst++ = *src++;    }    *dst =‘\0‘;        return rest;}

 

WY c語言進階