백준 9935번 C++

#include <iostream>
#include <string>

using namespace std;
const int MAX = 1000001;

int main(void) {
	char str[MAX];
	string s,bomb;
	int indexs = 0, flag, bomblen;

	cin >> s >> bomb;
	bomblen = bomb.length();
	for (int i = 0; i < s.length(); i++) {
		str[indexs++] = s[i];

		if ((indexs - bomblen) < 0)
			continue;

		if (str[indexs-1] == bomb[bomblen - 1]) {
			flag = 0;
			for (int j = 0; j < bomblen; j++) {
				if (str[indexs - j -1] != bomb[bomblen - j - 1]) {
					flag = -1;
					break;
				}
			}
			if (flag == 0) {
				indexs = indexs - bomblen;
			}
		}
	}
	if (indexs == 0)
		cout << "FRULA" << endl;
	else{
		for (int i = 0; i < indexs; i++)
			cout << str[i];
	cout << endl;
	}
	return 0;
}