Submission #800172

#	Time	Username	Problem	Language	Result	Execution time	Memory
800172		Andrey	Dreaming (IOI13_dreaming)	C++14	0 / 100	34 ms	12816 KiB

dreaming

#include "dreaming.h"
#include<bits/stdc++.h>
using namespace std;

int n,m;
vector<pair<int,int>> haha[100001];
vector<int> dp(100001,-1);

int dude(int a, int t, int d) {
    int ans = max(dp[a],d),big = 0,big2 = 0,b,c,e;
    for(int i = 0; i < haha[a].size(); i++) {
        if(haha[a][i].first != t) {
            b = haha[a][i].first;
            c = haha[a][i].second;
            if(dp[b]+c > big) {
                big2 = big;
                big = dp[b]+c;
            }
            else if(dp[b]+c > big2) {
                big2 = dp[b]+c;
            }
        }
    }
    for(int i = 0; i < haha[a].size(); i++) {
        if(haha[a][i].first != t) {
            b = haha[a][i].first;
            c = haha[a][i].second;
            if(c+dp[b] == big) {
                e = max(d,big2)+c;
            }
            else {
                e = max(d,big)+c;
            }
            ans = min(ans,dude(b,a,e));
        }
    }
    return ans;
}

void dfs(int a, int t) {
    dp[a] = 0;
    for(int i = 0; i < haha[a].size(); i++) {
        if(haha[a][i].first != t) {
            dfs(haha[a][i].first,a);
            dp[a] = max(dp[a],dp[haha[a][i].first]+haha[a][i].second);
        }
    }
}

int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
    n = N;
    m = M;
    for(int i = 0; i < m; i++) {
        haha[A[i]].push_back({B[i],T[i]});
        haha[B[i]].push_back({A[i],T[i]});
    }
    vector<int> wut(0);
    for(int i = 0; i < n; i++) {
        if(dp[i] == -1) {
            dfs(i,-1);
            wut.push_back(i);
        }
    }
    vector<int> wow(0);
    for(int i = 0; i < wut.size(); i++) {
        wow.push_back(dude(wut[i],-1,0));
    }
    sort(wow.begin(),wow.end());
    if(wow.size() == 1) {
        return wow[0];
    }
    else if(wow.size() == 2) {
        return wow[0]+wow[1]+L;
    }
    else {
        return max(wow[wow.size()-1]+wow[wow.size()-2]+L,wow[wow.size()-2]+wow[wow.size()-2]+2*L);
    }
}

Compilation message (stderr)

dreaming.cpp: In function 'int dude(int, int, int)':
dreaming.cpp:11:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |     for(int i = 0; i < haha[a].size(); i++) {
      |                    ~~^~~~~~~~~~~~~~~~
dreaming.cpp:24:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |     for(int i = 0; i < haha[a].size(); i++) {
      |                    ~~^~~~~~~~~~~~~~~~
dreaming.cpp: In function 'void dfs(int, int)':
dreaming.cpp:42:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |     for(int i = 0; i < haha[a].size(); i++) {
      |                    ~~^~~~~~~~~~~~~~~~
dreaming.cpp: In function 'int travelTime(int, int, int, int*, int*, int*)':
dreaming.cpp:65:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |     for(int i = 0; i < wut.size(); i++) {
      |                    ~~^~~~~~~~~~~~

• Subtask 1: 0 / 14
• Subtask 2: 0 / 10
• Subtask 3: 0 / 23
• Subtask 4: 0 / 18
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23