学习查找替换却不知道汉字是怎么样替换查找看见的高手指点下

/*  HELLO.C -- Hello, world */

#include "stdio.h"
#include "conio.h"
#include "string.h"
int replace(char *S,char *t1,char *t2,char *W)
{ char *p,*q,*t;
    strcpy(W,s) ;
    while(*W)
    {
        p = W;
        q = t1;
        while(*q)
        if(*q ==*p)
        {
            q++;
            p++;
        }
        else break;
        if(*q == '/0')
        {
            t = W;
            q = t2;
            while(*q)
            {
                *t = *q;
                t++;
                q++;
            }
        }
        else W++;

    }

}
main()
{
    char S[100], t1[100], t2[100],W[100];
    printf("/n请输入字符串S:"); gets(S);
    printf("/n请输入需要替换的源字符串S t1:"); gets(t1);
    printf("/n请输入需要替换的目标字符串S t2:"); gets(t2));
    if (strlen(t1)==strlen(t2)) {
        replace(S, t1, t2, W);
        printf("/nThe result is : %s/n", W);
    }
    else printf("Error : strlen(t1) != strlen(t2)/n");
   return 0;
}