Problem:
Score : 100 points

Problem Statement

AtCoder Inc. holds a contest every Saturday.

There are two types of contests called ABC and ARC, and just one of them is held at a time.

The company holds these two types of contests alternately: an ARC follows an ABC and vice versa.

Given a string S representing the type of the contest held last week, print the string representing the type of the contest held this week.

Constraints

S is ABC or ARC.

Input

Input is given from Standard Input in the following format:

S

Output

Print the string representing the type of the contest held this week.

Sample Input 1

ABC

Sample Output 1

ARC

They held an ABC last week, so they will hold an ARC this week.

Solution in C (Clang 10.0.0) (judge verdict: Wrong Answer)

#include<stdio.h>
int max(int a, int b);
int main(void) {
	int N,M,i,d;
	int H[100010]; int B[100010]; int A[100010]; 
	int S[100010];
	d = 0;
	scanf("%d", &N);
	scanf("%d", &M);
	for (i = 0; i < N; i++) {
		scanf("%d", &H[i]);

	}
	for (i = 0; i < N; i++) {
		S[i] = H[i];
	}
	for (i = 0; i < M; i++) {
		scanf("%d", &A[i]);
		scanf("%d", &B[i]);
	}
	for (i = 0; i < M; i++) {
		H[A[i] - 1] = max(H[A[i] - 1],H[B[i]-1]);
		H[B[i] - 1] = max(H[A[i] - 1], H[B[i] - 1]);

	}
	for (i = 0; i < N; i++) {
		if (H[i] == S[i]) {
			d++;
		}
	}
	printf("%d", d);
	return 0;
}
int max(int a, int b) {
	if (a > b) {
		return a;
	}
	else {
		return b;
	}
}