oj.uz

Submission #153033

# Submission time Handle Problem Language Result Execution time Memory
153033 2019-09-11T14:18:57 Z abacaba Valley (BOI19_valley) C++14
100 / 100
 389 ms 40772 KB 
#include <iostream>
#include <stdio.h>
#include <assert.h>
#include <string.h>
#include <stdio.h>
#include <algorithm>
#include <math.h>
#include <random>
#include <bitset>
#include <string>
#include <cstring>
#include <set>
#include <vector>
#include <map>
#include <stack>
using namespace std;

#define all(x) (x).begin(), (x).end()
#define max3(a, b, c) max(a, max(b, c))
#define min3(a, b, c) min(a, min(b, c))
#define mp make_pair
#define f first
#define se second
#define pb push_back
#define ppb pop_back
#define ll long long
#define ull unsigned long long
#define cntbit(x) __builtin_popcount(x)
#define endl '\n'
#define uset unordered_set
#define umap unordered_map
#define pii pair<int, int>
#define ld long double
#define pll pair<long long, long long>

struct edge {
	int u, v, w;
};

const ll inf = 2e18;
const int N = 1e5 + 15;
const int L = 20;
int n, s, q, t, tin[N], tout[N], last, up[L][N];
ll minn[N], d[N], dp[L][N];
vector <int> g[N];
vector <edge> e;
bool is[N];

inline bool upper(int a, int b) {
	return tin[a] <= tin[b] && tout[a] >= tout[b];
}

void build(int v, int p = t) {
	tin[v] = ++last;
	up[0][v] = p;
	for(int i = 1; i < L; ++i)
		up[i][v] = up[i-1][up[i-1][v]];
	if(is[v])
		minn[v] = d[v];
	for(int i : g[v]) {
		int to = (e[i].u == v ? e[i].v : e[i].u), w = e[i].w;
		if(to != p) {
			d[to] = d[v] + w;
			build(to, v);
			minn[v] = min(minn[v], minn[to]);
		}
	}
	tout[v] = ++last;
}

void build_dp(int v, int p = t) {
	dp[0][v] = minn[v];
	for(int i = 1; i < L; ++i)
		dp[i][v] = min(dp[i-1][v], dp[i-1][up[i-1][v]]);
	for(int i : g[v]) {
		int to = (e[i].u == v ? e[i].v : e[i].u);
		if(to != p)
			build_dp(to, v);
	}
}

inline ll get_lowest(int a, int b) {
	ll res = inf;
	for(int i = L - 1; i >= 0; --i)
		if(upper(a, up[i][b])) {
			res = min(res, dp[i][b]);
			b = up[i][b];
		}
	return min(res, dp[0][b]);
}


int main() {
	fill(minn, minn + N, inf);
	for(int i = 0; i < L; ++i)
		fill(dp[i], dp[i] + N, inf);
    scanf("%d%d%d%d", &n, &s, &q, &t);
    for(int i = 1; i < n; ++i) {
    	int u, v, w;
    	scanf("%d%d%d", &u, &v, &w);
    	e.pb({u, v, w});
    	g[u].pb(e.size() - 1);
    	g[v].pb(e.size() - 1);
    }
    for(int i = 1; i <= s; ++i) {
    	int x;
    	scanf("%d", &x);
    	is[x] = true;
    }
    build(t);
    for(int i = 1; i <= n; ++i) {
    	if(minn[i] != inf)
	    	minn[i] -= 2LL * d[i];
    }
    build_dp(t);
    while(q--) {
    	int i, x;
    	scanf("%d%d", &i, &x);
    	int u = e[i - 1].u, v = e[i - 1].v;
    	if(tin[u] > tin[v])
    		swap(u, v);
    	if(!upper(v, x)) {
    		puts("escaped");
    		continue;
    	}
    	ll val = get_lowest(v, x);
    	if(val < inf)
	    	printf("%lld\n", val + d[x]);
	    else
	    	puts("oo");
    }
    return 0;
}

Compilation message

valley.cpp: In function 'int main()':
valley.cpp:97:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d%d", &n, &s, &q, &t);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
valley.cpp:100:11: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
      scanf("%d%d%d", &u, &v, &w);
      ~~~~~^~~~~~~~~~~~~~~~~~~~~~
valley.cpp:107:11: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
      scanf("%d", &x);
      ~~~~~^~~~~~~~~~
valley.cpp:118:11: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
      scanf("%d%d", &i, &x);
      ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 19320 KB Output is correct
2 Correct 20 ms 19320 KB Output is correct
3 Correct 66 ms 19448 KB Output is correct
4 Correct 23 ms 19320 KB Output is correct

Subtask #2
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 19320 KB Output is correct
2 Correct 20 ms 19320 KB Output is correct
3 Correct 66 ms 19448 KB Output is correct
4 Correct 23 ms 19320 KB Output is correct
5 Correct 21 ms 19372 KB Output is correct
6 Correct 20 ms 19336 KB Output is correct
7 Correct 22 ms 19448 KB Output is correct
8 Correct 22 ms 19320 KB Output is correct
9 Correct 19 ms 19420 KB Output is correct
10 Correct 19 ms 19320 KB Output is correct
11 Correct 19 ms 19380 KB Output is correct
12 Correct 19 ms 19448 KB Output is correct
13 Correct 18 ms 19448 KB Output is correct
14 Correct 19 ms 19448 KB Output is correct

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 303 ms 33772 KB Output is correct
2 Correct 326 ms 33600 KB Output is correct
3 Correct 336 ms 33476 KB Output is correct
4 Correct 388 ms 34916 KB Output is correct
5 Correct 345 ms 34984 KB Output is correct
6 Correct 389 ms 36656 KB Output is correct

Subtask #4
41.0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 19320 KB Output is correct
2 Correct 20 ms 19320 KB Output is correct
3 Correct 66 ms 19448 KB Output is correct
4 Correct 23 ms 19320 KB Output is correct
5 Correct 21 ms 19372 KB Output is correct
6 Correct 20 ms 19336 KB Output is correct
7 Correct 22 ms 19448 KB Output is correct
8 Correct 22 ms 19320 KB Output is correct
9 Correct 19 ms 19420 KB Output is correct
10 Correct 19 ms 19320 KB Output is correct
11 Correct 19 ms 19380 KB Output is correct
12 Correct 19 ms 19448 KB Output is correct
13 Correct 18 ms 19448 KB Output is correct
14 Correct 19 ms 19448 KB Output is correct
15 Correct 303 ms 33772 KB Output is correct
16 Correct 326 ms 33600 KB Output is correct
17 Correct 336 ms 33476 KB Output is correct
18 Correct 388 ms 34916 KB Output is correct
19 Correct 345 ms 34984 KB Output is correct
20 Correct 389 ms 36656 KB Output is correct
21 Correct 278 ms 37048 KB Output is correct
22 Correct 293 ms 36744 KB Output is correct
23 Correct 301 ms 36816 KB Output is correct
24 Correct 348 ms 38316 KB Output is correct
25 Correct 380 ms 40772 KB Output is correct
26 Correct 283 ms 37264 KB Output is correct
27 Correct 295 ms 36904 KB Output is correct
28 Correct 303 ms 36864 KB Output is correct
29 Correct 338 ms 38040 KB Output is correct
30 Correct 343 ms 39212 KB Output is correct
31 Correct 279 ms 37132 KB Output is correct
32 Correct 293 ms 37032 KB Output is correct
33 Correct 313 ms 37032 KB Output is correct
34 Correct 335 ms 38440 KB Output is correct
35 Correct 341 ms 40748 KB Output is correct
36 Correct 319 ms 38184 KB Output is correct