Submission #930469

#	Time	Username	Problem	Language	Result	Execution time	Memory
930469		guagua0407	Aliens (IOI16_aliens)	C++17	25 / 100	188 ms	2652 KiB

aliens

//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
#include "aliens.h"
using namespace std;
#define ll long long
#define pii pair<int,int>
#define f first
#define s second
#define all(x) x.begin(),x.end()
#define _ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

int dx[4]={0,0,1,-1};
int dy[4]={1,-1,0,0};

void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}
const int mxn=505;
const ll inf=1e18;
vector<vector<ll>> dp(mxn,vector<ll>(mxn,inf));
vector<int> x,y;

ll cost(int l,int r){
    ll a=(y[r]-x[l]+1);
    ll b=(l==1?0:max(0,y[l-1]-x[l]+1));
    return a*a-b*b;
}

ll solve(int n,int m,int k){
    ll ans=inf;
    dp[0][0]=0;
    for(int t=1;t<=k;t++){
        for(int i=1;i<=n;i++){
            for(int j=0;j<i;j++){
                dp[i][t]=min(dp[i][t],dp[j][t-1]+cost(j+1,i));
            }
        }
        ans=min(ans,dp[n][t]);
    }
    return ans;
}

ll take_photos(int n, int m, int k, std::vector<int> r, std::vector<int> c){
    vector<pair<int,int>> vec(n);
    for(int i=0;i<n;i++){
        if(r[i]>c[i]) swap(r[i],c[i]);
        vec[i]={c[i],r[i]};
    }
    sort(all(vec));
    vector<pair<int,int>> st;
    for(int i=0;i<n;i++){
        while(!st.empty() and st.back().s>=vec[i].s){
            st.pop_back();
        }
        st.push_back(vec[i]);
    }
    x.push_back(-1);
    y.push_back(-1);
    for(auto v:st){
        x.push_back(v.s);
        y.push_back(v.f);
    }
    return solve(st.size(),m,k);
}
//maybe its multiset not set
//yeeorz
//laborz

Compilation message (stderr)

aliens.cpp: In function 'void setIO(std::string)':
aliens.cpp:16:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
aliens.cpp:17:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 4 / 4
• Subtask 2: 12 / 12
• Subtask 3: 9 / 9
• Subtask 4: 0 / 16
• Subtask 5: 0 / 19
• Subtask 6: 0 / 40