Submission #836002

#	Time	Username	Problem	Language	Result	Execution time	Memory
836002		cnastea	Awesome Arrowland Adventure (eJOI19_adventure)	C++14	100 / 100	199 ms	30728 KiB

adventure

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

int main(){
    int n, m;
    cin >> n >> m;
    char t;
    vector<pair<int, int>> a[n*m];
    for(int i = 0; i < n; i++){
        for(int j = 0; j < m; j++){
            cin >> t;
            if(t == 'N'){
                if(j < m-1) a[i*m+j].push_back({i*m+j+1, 1});
                if(i < n-1) a[i*m+j].push_back({(i+1)*m+j, 2});
                if(j > 0) a[i*m+j].push_back({i*m+j-1, 3});
                if(i > 0) a[i*m+j].push_back({(i-1)*m+j, 0});
            }
            if(t == 'E'){
                if(j < m-1) a[i*m+j].push_back({i*m+j+1, 0});
                if(i < n-1) a[i*m+j].push_back({(i+1)*m+j, 1});
                if(j > 0) a[i*m+j].push_back({i*m+j-1, 2});
                if(i > 0) a[i*m+j].push_back({(i-1)*m+j, 3});
            }
            if(t == 'S'){
                if(j < m-1) a[i*m+j].push_back({i*m+j+1, 3});
                if(i < n-1) a[i*m+j].push_back({(i+1)*m+j, 0});
                if(j > 0) a[i*m+j].push_back({i*m+j-1, 1});
                if(i > 0) a[i*m+j].push_back({(i-1)*m+j, 2});
            }
            if(t == 'W'){
                if(j < m-1) a[i*m+j].push_back({i*m+j+1, 2});
                if(i < n-1) a[i*m+j].push_back({(i+1)*m+j, 3});
                if(j > 0) a[i*m+j].push_back({i*m+j-1, 0});
                if(i > 0) a[i*m+j].push_back({(i-1)*m+j, 1});
            }
        }
    }
    int d[n*m];
    multiset<pair<int, int>> s;
    for(int i = 1; i < n*m; i++){
        d[i] = 1e9;
        s.insert({1e9, i});
    }
    s.insert({0, 0});
    d[0] = 0;
    while(s.size() > 0){
        pair<int, int> p = *s.begin();
        int v = p.second;
        s.erase(p);
        for(int i = 0; i < a[v].size(); i++){
            if(d[v] + a[v][i].second < d[a[v][i].first]){
                s.erase({d[a[v][i].first], a[v][i].first});
                d[a[v][i].first] = d[v] + a[v][i].second;
                s.insert({d[a[v][i].first], a[v][i].first});
            }
        }
    }
    if(d[m*n-1] == 1e9) cout << -1;
    else cout << d[m*n-1];
}

Compilation message (stderr)

adventure.cpp: In function 'int main()':
adventure.cpp:50:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |         for(int i = 0; i < a[v].size(); i++){
      |                        ~~^~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 12 / 12
• Subtask 4: 16 / 16
• Subtask 5: 50 / 50