Submission #1362342

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Source Code Expand

#include <bits/stdc++.h>  

using namespace std;

#define FOR(i, j, k) for(int i = j; i < k; ++i)
#define rep(i, j) FOR(i, 0, j)
#define FORr(i, j, k) for(int i = j; i >= k; --i)
#define repr(i, j) FOR(i, j, 0)
#define INF (1 << 30)
const int MOD = 1e9 + 7;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> P;
typedef pair<P, int> Pi;

int N, K, use[26], unuse[26];
string s, ans;

int main() {
	cin >> N >> K >> s;
	rep(i, s.size()) ++use[s[i] - 'a'];
	rep(i, s.size()) {
		rep(j, 26) {
			if(!use[j]) continue;
			--use[j];
			int cnt = (s[i] == j + 'a') ? N - 1 : N;
			rep(k, i) if(s[k] == ans[k]) --cnt;
			fill(unuse, unuse + 26, 0);
			FOR(k, i + 1, s.size()) ++unuse[s[k] - 'a'];
			rep(k, 26) cnt -= min(use[k], unuse[k]);
			if(cnt < K + 1) {
				ans += j + 'a';
				break;
			}
			++use[j];
		}
	}
	cout << ans << endl;
	return 0;
}

Submission Info

Judge Result