Submission #773390

#	Time	Username	Problem	Language	Result	Execution time	Memory
773390		ttamx	Aliens (IOI16_aliens)	C++14	12 / 100	93 ms	2328 KiB

aliens

#include "aliens.h"
#include<bits/stdc++.h>

using namespace std;

typedef long long ll;

const int N=1e5+5;
const int M=1e6+6;
const int dbg=false;

int l[N],r[N];
ll val[N];
int mn[M];
set<pair<int,int>> s;

long long take_photos(int n, int m, int k, vector<int> r, vector<int> c) {
    for(int i=0;i<m;i++)mn[i]=m;
    for(int i=0;i<n;i++){
        int x=r[i],y=c[i];
        int st=min(x,y),ed=max(x,y);
        mn[ed]=min(mn[ed],st);
    }
    for(int i=0;i<m;i++){
        if(mn[i]==m)continue;
        while(!s.empty()&&prev(s.end())->first>=mn[i])s.erase(prev(s.end()));
        s.emplace(mn[i],i);
    }
    if(dbg){
        for(auto [x,y]:s)cerr << "(" << x << "," << y << ") ";
        cerr << "\n";
    }
    n=0;
    for(auto [x,y]:s){
        n++;
        l[n]=x;
        r[n]=y;
        ll sz=r[n]-l[n]+1;
        val[n]=sz*sz;
    }
    for(int i=1;i<n;i++){
        ll res=max(0,r[i]-l[i+1]+1);
        val[i]-=res*res;
    }
    vector<vector<ll>> dp(n+1,vector<ll>(k+1));
    for(int i=1;i<=n;i++){
        dp[i][0]=1e18;
        for(int j=1;j<=k;j++){
            dp[i][j]=dp[i-1][j-1]+val[i];
            for(int x=1;x<i;x++){
                ll sz=r[i]-l[x]+1;
                dp[i][j]=min(dp[i][j],dp[x-1][j-1]+sz*sz);
            }
        }
    }
    return dp[n][k];
}

Compilation message (stderr)

aliens.cpp: In function 'long long int take_photos(int, int, int, std::vector<int>, std::vector<int>)':
aliens.cpp:30:18: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   30 |         for(auto [x,y]:s)cerr << "(" << x << "," << y << ") ";
      |                  ^
aliens.cpp:34:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   34 |     for(auto [x,y]:s){
      |              ^

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