Submission #864359

#	Time	Username	Problem	Language	Result	Execution time	Memory
864359		maks007	Paths (BOI18_paths)	C++14	70 / 100	468 ms	42092 KiB

paths

#include "bits/stdc++.h"

using namespace std;

#define int long long

vector <int> color;
vector <vector <int>> cntColor, g, dp;

signed main () {
	int n, m, k;
	cin >> n >> m >> k;
	color.resize(n);
	cntColor.resize(n, vector <int> (k + 1, 0));
	g.resize(n);
	for(int i = 0; i < n; i ++) cin >> color[i];
	for(int i = 0, u, v; i < m; i ++) {
		cin >> u >> v;
		u --, v --;
		g[u].push_back(v);
		g[v].push_back(u);
		cntColor[u][color[v]] ++;
		cntColor[v][color[u]] ++;
	}
	int ans = 0;
	for(int color2 = 1; color2 <= k; color2 ++) {
		for(int i = 0; i < n; i ++) {
			if(color[i] == color2) {
				for(int color1 = 1; color1 <= k; color1 ++) {
					if(color1 == color2) continue;
					ans += cntColor[i][color1];
					if(k == 2) continue;
					for(int color3 = color1 + 1; color3 <= k; color3 ++) {
						if(color3 == color2) continue;
						ans += 2 * (cntColor[i][color1] * cntColor[i][color3]);
					}
				}
			}
		}
  	}
  	if(k >= 4) {
  		for(int v = 0; v < n; v ++) {
  			for(auto u : g[v]) {
  				if(color[u] == color[v]) continue;
  				for(int i = 1; i <= k; i ++) {
  					if(i == color[u] || color[v] == i) continue;
  					for(int j = 1; j <= k; j ++) {
  						if(j == i || j == color[u] || j == color[v]) continue;
  						ans += cntColor[v][i] * cntColor[u][j];
  					}
  				}	
  			}
  		}
  	}
  	if(k >= 5) {
		dp.resize(n, vector <int> (1 << (k + 1)));
  		for(int i = 0; i < n; i ++) {
  			for(int color1 = 1; color1 <= k; color1 ++) {
  				for(int color2 = color1 + 1; color2 <= k; color2 ++) {
  					int cnt = 0;
  					for(auto u : g[i]) {
  						if(color[u] == color1 || color[u] == color2) cnt ++;
  					}
  					dp[i][(1 << color1) ^ (1 << color2)] = cnt;
  				}
  			}
  		}
  		
  		for(int mid = 0; mid < n; mid ++) {
  			for(auto l : g[mid]) {
  				if(color[mid] == color[l]) continue;
  				for(auto r : g[mid]) {
  					if(color[mid] == color[r] || color[l] == color[r]) continue;
  					int bitVal = ((1 << (k + 1)) - 1) ^ (1 << color[mid]) ^ (1 << color[l]) ^ (1 << color[r]);
  					ans += dp[l][bitVal] * dp[r][bitVal];
  				}
  			}
  		}
  	}
  	cout << ans;
	return 0;
}

• Subtask 1: 23 / 23
• Subtask 2: 20 / 20
• Subtask 3: 27 / 27
• Subtask 4: 0 / 30