/*
 * Solution Template for Election II
 * 
 * Australian Informatics Olympiad 2022
 * 
 * This file is provided to assist with reading of input and writing of output 
 * for the problem. You may modify this file however you wish, or
 * you may choose not to use this file at all.
 */

#include <cstdio>

/* N is the number of votes. */
int N;

/* votes contains the sequence of votes. */
char votes[100005];

char answer;

int main(void) {
    /* Read the value of N and the votes. */
    scanf("%d", &N);
    scanf("%s", votes);

    /*
     * TODO: This is where you should compute your solution. Store the winning
     * candidate ('A', 'B' or 'C'), or 'T' if there is a tie, into the variable
     * answer.
     */

    /* Write the answer. */
    printf("%c\n", answer);

    return 0;
}