CF - A. String Building

2, 3可以组成大于等于2和3的一切数，所以除了1以外的情况不需要考虑

#include<bits/stdc++.h>
using namespace std;
const int N = 1e5 + 10;
bool t[N];

int main() {
	int t;
	cin >> t;
	while (t --) {
		string s;
		cin >> s;
		int a = 0, b = 0;
		bool tt = false;
		for (int i = 0; i < s.size(); i ++) {
			if (s[i] == 'a') {
				a ++;
				if (b == 1) {
					printf("No\n");
					b = 0, a = 0;
					tt = true;
					break;
				}
				b = 0;
			}
			if (s[i] == 'b') {
				b ++;
				if (a == 1) {
					printf("No\n");
					b = 0, a = 0;
					tt = true;
					break;
				}
				a = 0;
			}
		}
		if (a == 1) {
			printf("No\n");
			continue;
		} else if (b == 1) {
			printf("No\n");
			continue;
		}
		if (!tt)printf("Yes\n");
	}
	return 0;
}