different word

#include<stdio.h>
#include<string.h>

int main()
{
    int t, i, j, count, n, flag;
    char grid[1005][105], str[105];
    scanf("%d", &t);
    while(t--){
        scanf("%d", &n);
        memset(grid, '\0', sizeof(grid));//setting all elements to NULL
        count = 0;
        for(i = 0; i < n; i++){
            scanf("%s", str);
            flag = 0;//no match found
            for(j = 0; j < i; j++){
                if(strcmp(grid[j], str) == 0){
                    flag = 1;// at least one match found
                    break;
                }
            }

            if(flag == 0){//if no match found
                strcpy(grid[j], str);
                count++;
            }
        }
        printf("%d\n", count);
    }
    return 0;
}