oj.uz

답안 #55151

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
55151 2018-07-06T06:48:21 Z 윤교준(#1528) 날다람쥐 (JOI14_ho_t4) C++11
0 / 100
 2000 ms 10760 KB 
#include <bits/stdc++.h>
#define pb push_back
#define eb emplace_back
#define sz(V) ((int)(V).size())
#define allv(V) ((V).begin()),((V).end())
#define befv(V) ((V)[sz(V)-2])
#define sorv(V) sort(allv(V))
#define revv(V) reverse(allv(V))
#define univ(V) (V).erase(unique(allv(V)),(V).end())
#define upmax(a,b) (a)=max((a),(b))
#define upmin(a,b) (a)=min((a),(b))
#define rb(x) ((x)&(-(x)))
#define INF (0x3f3f3f3f)
#define INFLL (0x3f3f3f3f3f3f3f3fll)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<int, ll> pil;
typedef pair<ll, int> pli;

const int MAXN = 100005;
const int MAXM = 300005;

vector<pii> G[MAXN];

ll D[MAXN];

int A[MAXM], B[MAXM], C[MAXM];

int H[MAXN];

ll Ans = INFLL;
int N, M, X, MXH;

ll f(int h) {
	priority_queue<pli, vector<pli>, greater<pli>> PQ;

	fill(D, D+N+1, INFLL);
	D[1] = 0;
	PQ.push(pli(0, 1));

	for(; !PQ.empty();) {
		int idx; ll dst; tie(dst, idx) = PQ.top(); PQ.pop();
		if(D[idx] < dst) continue;

		for(pii e : G[idx]) {
			int nidx = e.first; ll ndst = dst + e.second;
			if(H[nidx] < ll(h) - ndst) continue;
			if(D[nidx] <= ndst) continue;
			D[nidx] = ndst;
			PQ.push(pli(ndst, nidx));
		}
	}

	return D[N]*2 + abs(X - h) + H[N] - h;
}

int main() {
    //freopen("input.txt", "r", stdin);
	ios::sync_with_stdio(false);

	cin >> N >> M >> X;
	for(int i = 1; i <= N; i++) cin >> H[i];
	for(int i = 1; i <= M; i++) cin >> A[i] >> B[i] >> C[i];

	for(int i = 1, a, b, c; i <= M; i++) {
		a = A[i]; b = B[i]; c = C[i];
		if(c <= H[a]) G[a].eb(b, c);
		if(c <= H[b]) G[b].eb(a, c);
	}

	if(INFLL <= f(0)) {
		puts("-1");
		return 0;
	}

	{
		int s = 0, e = H[1]; for(int m; s < e;) {
			m = (s+e+1)/2;
			if(INFLL <= f(m)) e = m-1;
			else s = m;
		}

		MXH = s;
	}

	{
		int s = 0, e = MXH; for(int m; 5 < e-s;) {
			m = (s+e)/2;
			ll t1 = f(m), t2 = f(m+1);
			if(t2 < t1) s = m+1;
			else e = m;
			upmin(Ans, min(t1, t2));
		}

		for(int i = s; i <= e; i++)
			upmin(Ans, f(i));
	}

	cout << Ans << endl;
	return 0;
}

Subtask #1
0 / 25.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 2808 KB Output is correct
2 Correct 8 ms 2920 KB Output is correct
3 Incorrect 9 ms 2920 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
0 / 25.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 2091 ms 10760 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #3
0 / 50.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 2808 KB Output is correct
2 Correct 8 ms 2920 KB Output is correct
3 Incorrect 9 ms 2920 KB Output isn't correct
4 Halted 0 ms 0 KB -