oj.uz

답안 #244273

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
244273 2020-07-03T13:06:27 Z pit4h Olympic Bus (JOI20_ho_t4) C++14
0 / 100
 235 ms 4100 KB 
#include<bits/stdc++.h>
using namespace std;

const int N = 201, M = 5e4+1;
const long long INF = 1e12+1;
int n, m, u[M], v[M];
long long c[M], d[M];
long long G[N][N], W[N][N], E[N][N][2];
long long skip[N][N][2], skipt[N][N][2]; // 0 -> (n, 1), 1 -> (1, n)

void calculate_skip(int p, int q) {
	for(int i=1; i<=n; ++i) {
		for(int j=1; j<=n; ++j) {
			skip[i][j][p==1] = INF;
		}
	}
	//calc skip here

	for(int k=1; k<=n; ++k) {
		if(k==q) continue;
		vector<bool> vis(n+1);
		vis[k] = 1;
		priority_queue<pair<long long, int>> Q;
		Q.push({0, q});
		skip[q][k][p==1] = 0;
		while(Q.size()) {
			auto cur = Q.top();
			Q.pop();
			if(vis[cur.second]) continue;
			vis[cur.second] = 1;

			for(int i=1; i<=n; ++i) {
				if(i==k) continue;
				if(skip[i][k][p==1] > cur.first + W[i][cur.second]) {
					Q.push({cur.first + W[i][cur.second], i});
					skip[i][k][p==1] = cur.first + W[i][cur.second];
				}
			}
		}
	}

	for(int i=1; i<=n; ++i) {
		for(int j=1; j<=n; ++j) {
			skipt[i][j][p==1] = INF;
		}
	}
	//calc skip here

	for(int k=1; k<=n; ++k) {
		if(k==q) continue;
		vector<bool> vis(n+1);
		vis[k] = 1;
		priority_queue<pair<long long, int>> Q;
		Q.push({0, q});
		skipt[q][k][p==1] = 0;
		while(Q.size()) {
			auto cur = Q.top();
			Q.pop();
			if(vis[cur.second]) continue;
			vis[cur.second] = 1;

			for(int i=1; i<=n; ++i) {
				if(i==k) continue;
				if(skipt[i][k][p==1] > cur.first + W[cur.second][i]) {
					Q.push({cur.first + W[cur.second][i], i});
					skipt[i][k][p==1] = cur.first + W[cur.second][i];
				}
			}
		}
	}
}

long long solve(int p, int q) {

	long long ans = INF;

	for(int i=0; i<m; ++i) {

		long long path[2] = {0, 0};

		path[1] = skipt[v[i]][u[i]][p==1] + c[i] + d[i] + skip[u[i]][v[i]][p==n];
		path[0] = INF;
		
		if(E[u[i]][v[i]][0] != c[i]) {
			path[0] = min(path[0], G[p][u[i]] + E[u[i]][v[i]][0] + G[v[i]][q]);
		}
		else {
			path[0] = min(path[0], G[p][u[i]] + E[u[i]][v[i]][1] + G[v[i]][q]);
		}
		if(G[p][u[i]] + W[u[i]][v[i]] + G[v[i]][q] > G[p][q]) path[0] = G[p][q];

		else {
			path[0] = min(path[0], skip[p][u[i]][p==1]);
			for(int k=1; k<=n; ++k) {
				if(k != u[i] && k != v[i]) {
					path[0] = min(path[0], G[p][u[i]] + W[u[i]][k] + skip[k][u[i]][p==1]);
				}
			}
		}
		ans = min(ans, path[0] + path[1]);
	}
	return ans;
}

int main() {

	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	cin>>n>>m;

	for(int i=1; i<=n; ++i) {
		for(int j=1; j<=n; ++j) {
			G[i][j] = INF;
			W[i][j] = INF;
			E[i][j][0] = E[i][j][1] = INF;
		}
		G[i][i] = 0;
	}

	for(int i=0; i<m; ++i) {
		cin>>u[i]>>v[i]>>c[i]>>d[i];
		G[u[i]][v[i]] = min(G[u[i]][v[i]], c[i]);
		W[u[i]][v[i]] = min(W[u[i]][v[i]], c[i]);
		if(E[u[i]][v[i]][0] > c[i]) {
			E[u[i]][v[i]][1] = E[u[i]][v[i]][0];
			E[u[i]][v[i]][0] = c[i];
		}
		else if(E[u[i]][v[i]][1] > c[i]) {
			E[u[i]][v[i]][1] = c[i];
		}
	}

	for(int k=1; k<=n; ++k) {
		for(int i=1; i<=n; ++i) {
			for(int j=1; j<=n; ++j) {
				G[i][j] = min(G[i][j], G[i][k] + G[k][j]);	
			}
		}
	}
	
	calculate_skip(1, n);
	calculate_skip(n, 1);

	long long ans = min({G[1][n]+G[n][1], solve(1, n), solve(n, 1)});
	if(ans >= INF) cout<<-1;
	else cout<<ans;
}

Subtask #1
0 / 5.0

# 결과 실행 시간 메모리 Grader output
1 Correct 77 ms 2944 KB Output is correct
2 Correct 22 ms 2944 KB Output is correct
3 Correct 93 ms 2936 KB Output is correct
4 Correct 90 ms 2936 KB Output is correct
5 Incorrect 7 ms 768 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #2
0 / 11.0

# 결과 실행 시간 메모리 Grader output
1 Correct 222 ms 4088 KB Output is correct
2 Correct 233 ms 4088 KB Output is correct
3 Correct 235 ms 4088 KB Output is correct
4 Incorrect 105 ms 2936 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #3
0 / 21.0

# 결과 실행 시간 메모리 Grader output
1 Correct 78 ms 2936 KB Output is correct
2 Correct 36 ms 2936 KB Output is correct
3 Correct 126 ms 3852 KB Output is correct
4 Correct 31 ms 2816 KB Output is correct
5 Correct 149 ms 4100 KB Output is correct
6 Correct 5 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Incorrect 97 ms 4092 KB Output isn't correct
9 Halted 0 ms 0 KB -

Subtask #4
0 / 63.0

# 결과 실행 시간 메모리 Grader output
1 Correct 77 ms 2944 KB Output is correct
2 Correct 22 ms 2944 KB Output is correct
3 Correct 93 ms 2936 KB Output is correct
4 Correct 90 ms 2936 KB Output is correct
5 Incorrect 7 ms 768 KB Output isn't correct
6 Halted 0 ms 0 KB -