c语言

char* replaceSpace(char* s ) {
    char str[5000] = {};
    int j = 0;
    for(int i = 0; s[i] != '\0'; ++i) {
        if(s[i] == ' ') {
            str[j++] = '%';
            str[j++] = '2';
            str[j++] = '0';
        }
        else {
            str[j++] = s[i];
        }
    }
    str[j++] = '\0';
    return str;
}