#include <stdio.h>

#include <string.h>

#define Num 1000

int main()

{

    int  c,i,j = 0,m = 0,n = 0,k,count1 = 0,count2 = 0,w,h = 0,l = 0,flag2 = 0;

    char s[Num],t[Num],str[Num] = {'\0'};

    int  number[Num],number2[Num],flag = 0;

    printf("Please input a string:\n");

    while((c = getchar()) != EOF && c != '\n' && count1 < Num)

    {

        s[count1] = c;

        count1++;

    }

    printf("Please input another string:\n");

     while((c = getchar()) != EOF && c != '\n' && count2 < Num)

    {

        t[count2] = c;

        count2++;

    }

    for(i = 0;i < count1;i++)

    {

        flag = 0;

        for(k = 0;k < m;k++)

        {

            if(s[i] == str[k])

                {

                    flag = 1;

                    break;

                }

        }

        if(flag == 0)

        {

            for(j = 0;j < count2;j++)

            {

                if(s[i] == t[j])

                {

                    str[m++] = s[i];

                    number[n++] = i;

                    number2[h++] = j;

                    break;

                }

            }

        }

    }

    printf("The first location in str1 where any character from str2 occurs\n");

    for(w = 0;w < count2;w++)

        {

            flag2 = 0;

            for(l = 0;l < m;l++)

                {

                    if(w == number2[l])

                    {

                        printf("%c",str[l]);

                        printf(",%d\n",number[l]);

                        flag2 = 1;

                        break;

                    }

                }

            if(flag2 == 0)

                 printf("%c,-1\n",t[w]);

        }

    return 0;

}

费了好大劲，完成期间错误百出！要仔细点啊。