参考答案

void StrReplace(char *strSrc, char *strFind, char *strReplace);
#define M 100;
void main()
{
    char s[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    char s1[] = "RST";
    char s2[] = "ggg";
    StrReplace(s, s1, s2);
    printf("%s\n", s);
    return 0;
}
void StrReplace(char *strSrc, char *strFind, char *strReplace)
{
    int i = 0;
    int j;
    int n = strlen(strSrc);
    int k = strlen(strFind);
    for (i = 0; i
{
    if (*(strSrc + i) == *strFind)
        {
            for (j = 0; j
        {
            if (*(strSrc + i + j) == *(strFind + j))
                {
                    *(strSrc + i + j) = *(strReplace + j);
                }
                else continue;
            }
        }
    }
}