Submission #170569

#	Time	Username	Problem	Language	Result	Execution time	Memory
170569		Swan	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	57 / 100	79 ms	1400 KiB

skyscraper

#include <bits/stdc++.h>
#define stop system("pause")
#define stop2 char o; cin >> o
#define INP freopen("pcb.in","r",stdin)
#define OUTP freopen ("pcb.out","w",stdout)
using namespace std;

const int maxn = 210;

int ans[2001];
vector<int> qwe[2001];
vector<pair<int,int> > v;
priority_queue<pair<int,int> > q;
int n,m;

void solve(int start){
    ans[start] = 0;
    q.push({0,start});
    while(q.size()){
        //stop;
        int now = q.top().second;
        int dist = -q.top().first;
        //cerr << now << endl;
        q.pop();
        if(dist > ans[now])continue;
        //cout << now << ' ' << ans[now] << endl;
        for(int i(0); i < qwe[now].size();i++){
            int w = qwe[now][i];
            int p = qwe[now][i];
            int cnt = 1;
            while(now+p < n){
                if(ans[now+p] > ans[now]+cnt){
                    ans[now+p] = ans[now]+cnt;
                    q.push({-ans[now+p],now+p});
                }
                cnt++;
                p+=w;
            }
            p = -w;
            cnt = 1;
            while(now+p >= 0){
                if(ans[now+p] > ans[now]+cnt){
                    ans[now+p] = ans[now]+cnt;
                    q.push({-ans[now+p],now+p});
                }
                cnt++;
                p-=w;
            }
        }
    }
}

main(){
    ios_base::sync_with_stdio(0);
    cin >> n >> m;
    for(int i(0);i<=n;i++)ans[i] = 1e9;
    int need;
    for(int i(0); i < m;i++){
        int b,p; cin >> b >> p;
        v.push_back({b,p});
        qwe[b].push_back(p);
        if(i==1)need = b;
    }
    solve(v[0].first);
    if(ans[need] == 1e9)cout << -1;
    else cout << ans[need];
}

/*
5 3
0 2
1 1
4 1
*/

Compilation message (stderr)

skyscraper.cpp: In function 'void solve(int)':
skyscraper.cpp:27:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i(0); i < qwe[now].size();i++){
                       ~~^~~~~~~~~~~~~~~~~
skyscraper.cpp: At global scope:
skyscraper.cpp:53:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main(){
      ^
skyscraper.cpp: In function 'int main()':
skyscraper.cpp:65:16: warning: 'need' may be used uninitialized in this function [-Wmaybe-uninitialized]
     if(ans[need] == 1e9)cout << -1;
        ~~~~~~~~^

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 14 / 14
• Subtask 4: 21 / 21
• Subtask 5: 0 / 43