Submission #385213

#	Time	Username	Problem	Language	Result	Execution time	Memory
385213		ritul_kr_singh	PIN (CEOI10_pin)	C++17	0 / 100	7 ms	2156 KiB

pin

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define sp << ' ' <<
#define nl << '\n'

int mask;

bool comp(string x, string y){
	for(int i=0; i<4; ++i){
		if(((1<<i)&mask) and x[i]!=y[i]) return x[i]<y[i];
	}
	return false;
}

bool equal(string x, string y){
	return comp(x, y)==comp(y, x);
}

signed main(){
	cin.tie(0)->sync_with_stdio(0);
	int n, d, ans = 0; cin >> n >> d;
	string a[n]; for(auto &i : a) cin >> i;
	d = n-d;

	for(mask=0; mask<16; ++mask){
		int cnt = 0;
		for(int i=0; i<4; ++i) if((1<<i)&mask) ++cnt;
		if(cnt<d) continue;

		sort(a, a+n, comp);
		for(int i=0; i<n; ++i){
			int j = i;
			while(j+1<n and equal(a[i], a[j+1])) ++j;
			ans += ((cnt-d)%2 ? -1 : 1) * ((j-i+1)*(j-i))/2;
			i = j;
		}
	}
	cout << ans;
}

• Subtask 1: 0 / 100