#include <stdio.h>
int main(void)
{
    char f[81];
    int a=0;
    char ch;
   
    puts("input the array");
    gets(f);
    puts("put a  char");
    ch=getchar();
   
    while(f[a]!='\0')
    {
        if(f[a]==ch)     
        printf("the first location is %d\n",a);
        a++;
    }
    printf("there is no %s in the array\n",ch);
    return 0;
}

没有分不予以解答~

#include<iostream>
#include<string>
using namespace std;
int main()
{
   cout<<"pleas input one string"<<endl;
   string a;
   cin>>a;
   int i,j=0;
   char ch;
   cin>>ch;

   for(i=0;a[i]!='\0';++i)
    {
       if(a[i]==ch)
        {cout<<"the location of"<<ch<<"is"<<i<<endl;
          j=1;
        }
    }
   if(j==0)
   cout<<"there is no "<<ch<<" inside"<<endl;
   return 0;
}
Here is the code, hope it will give you some suggestions.

这个程序想得到的结果是什么？

#include <stdio.h>
#include<string.h>
int main(void)
{
    char f[81];
    int a=0;
    char ch;
    
    puts("input the array");
    gets(f);
//    f[strlen(f)]='\0';
    puts("put a  char");
    ch=getchar();
    
    while(f[a]!='\0')
    {
        if(f[a]==ch)
        {
         printf("the first location is %d\n",a+1);
         break;
        }
        a++;
    }
    if(a==strlen(f))
    {
    printf("there is no %c in the array\n",ch);
    }
    return 0;
}

谢谢各位。。。

f最后的字符应该是回车吧。。不是EOF。。。对吧？

while(f[a]!='\0')
    {
        if(f[a]==ch)     
       { printf("the first location is %d\n",a);
         break;
        }
        a++;
    }