#include <stdlib.h>
#include <iostream>
using namespace std;

int main()
{
    int n, cnt = 0;
    register int j;
    char shop[1001][31];
    char used[5] = "stop";

    cin >> n;
    for(register int i = 0; i < n; i++)
        cin >> shop[i];

    for(register int i = 0; i < n; i++)
    {
        if(shop[i] == "stop")
            break;
        for(j = i + 1; j <= n; j++)
        {
            if(strcmp(shop[j], "stop") != 0)
                if(strcmp(shop[i], shop[j]) == 0)
                {
                    cnt++;
                    strcpy(shop[j], "stop");
                }
        }
    }

    cout << cnt;
}

The same problem:
#include <stdio.h>
#include <string.h>

void main(void)
{
    char n[1000][31]={'/'};
    int i,y,qw,bayan=0;

    scanf("%d",&qw);

    for(i=0;i<qw;i++)
    {    scanf("%s",&n[i][0]);
        for(y=0;y<=i-1;y++)
            if(strcmp(n[y],n[i])==0)
            {    n[y][0]='/';
                bayan++;}
    }
    printf("%d",bayan);
}

Edited by author 20.01.2010 11:12

Edited by author 20.01.2010 11:12

"The brands are the strings of Latin letters and blanks"!
scanf doesn't read blanks ("aaa bbb" - two words for scanf).

I use

getline(cin,str); // !!!
     for(int i=0; i<n;i++){getline(cin,str)...

and Accepted.