Submission #418617

#	Time	Username	Problem	Language	Result	Execution time	Memory
418617		snasibov05	Race (IOI11_race)	C++14	31 / 100	432 ms	262148 KiB

race

#include "race.h"
#include <vector>

using namespace std;

#define oo 1000000000
#define pii pair<int, int>
#define pb push_back
#define f first
#define s second

int ans = oo;
vector<vector<pii>> ed;
vector<vector<int>> dp;

void dfs(int cur, int pr, int k){
    dp[cur][0] = 0;
    for (auto [to, dist] : ed[cur]){
        if (to == pr) continue;
        dfs(to, cur, k);

        for (int i = 0; i <= k; ++i) {
            if (i - dist >= 0 && i <= k) ans = min(ans, dp[to][i - dist] + dp[cur][k - i] + 1);
        }

        for (int i = 0; i <= k; ++i) {
            if (i - dist >= 0) dp[cur][i] = min(dp[cur][i], dp[to][i-dist] + 1);
        }
    }

}

int best_path(int n, int k, int h[][2], int l[]){
    ed.resize(n);
    dp.resize(n);
    dp.assign(n, vector<int>(k+1, oo));
    for (int i = 0; i < n - 1; ++i) {
        ed[h[i][0]].pb({h[i][1], l[i]});
        ed[h[i][1]].pb({h[i][0], l[i]});
    }
    dfs(0, -1, k);
    if (ans == oo) ans = -1;

    return ans;

}

Compilation message (stderr)

race.cpp: In function 'void dfs(int, int, int)':
race.cpp:18:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   18 |     for (auto [to, dist] : ed[cur]){
      |               ^

• Subtask 1: 9 / 9
• Subtask 2: 0 / 12
• Subtask 3: 22 / 22
• Subtask 4: 0 / 57