Submission #385220

#	Time	Username	Problem	Language	Result	Execution time	Memory
385220		ritul_kr_singh	PIN (CEOI10_pin)	C++17	100 / 100	487 ms	2028 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; cin >> n >> d;
	string a[n]; for(auto &i : a) cin >> i;
	int ans[5] = {};

	int c[5][5];
	c[4][0] = c[4][4] = 1, c[4][1] = c[4][3] = 4, c[4][2] = 6;
	c[3][0] = c[3][3] = 1, c[3][1] = c[3][2] = 3;
	c[2][0] = c[2][2] = 1, c[2][1] = 2;
	c[1][0] = c[1][1] = 1;
	c[0][0] = 1;

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

		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] += ((j-i+1)*(j-i))/2;
			i = j;
		}
	}
	int j = -1, res = 0;
	for(int i=4-d; i<5; ++i){
		j = -j;
		res += ans[i] * j * c[i][4-d];
	}
	cout << res;
}

• Subtask 1: 100 / 100