#include<stdio.h>
#include<string.h>
char ha[1<<21],k[256];
int main(int argc,char *argv[]){
    int flg;
    int val,s,t;
    char c;
    k['T'] = 1;
    k['G'] = 2;
    k['C'] = 3;
    k['A'] = 4;
    
    scanf("%d", &val);
    getchar();
    while (val--) {
        s = 0;
        t = 1;
        flg = ( c = getchar() ) == 'i';
        while ( ( c = getchar() ) != ' ' );
        while ( ( c = k[getchar()] ) != 0 ) {
            s += c * t;
            t *= 4;
        }
        if (flg) ha[s] = 1; else puts( ha[s] ? "yes" : "no" );
    }
    return 0;
}