Submission #135649

#	Time	Username	Problem	Language	Result	Execution time	Memory
135649		ckodser	Aliens (IOI16_aliens)	C++14	0 / 100	2 ms	504 KiB

aliens

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

#define ll int
#define pb push_back
#define mp make_pair
#define ld long double
#define F first
#define S second
#define pii pair<ll,ll>

using namespace :: std;

const ll maxn=100;
const ll maxk=110;
const ll inf=1e9+900;
const ll logg=20;

ll tav2(ll x){
    return x*x;
}

ll mx[maxn];
ll dp[maxn][maxk];
vector<ll> imp;
ll ff[maxn][logg];
ll tt[maxn];
ll C[maxn][maxn];

ll findMn(ll l,ll r){
    if(l<0)l=0;
    if(r>=maxn)r=maxn-1;
    if(l>r)return 0;
    ll tol=r-l+1;
    return min(ff[l][tt[tol]],ff[r-(1<<tt[tol])+1][tt[tol]]);
}
ll cost(ll i,ll x){
    ll t=findMn(x+1,i);
    if(t>x || mx[x]>=t){
	return tav2(i-t+1);
    }
    return tav2(i-t+1)-tav2(x-t+1);
}
void update(ll j,ll l,ll r,ll L,ll R){
    if(l>=r)return;
    ll mid=(l+r)/2;
    if(mid==0){
	dp[0][j]=0;
	return ;
    }
    pii best=mp(inf,inf);
    for(ll i=L;i<R ;i++){
	best=min(best,mp(dp[i][j-1]+C[i][mid],i));
    }
    dp[mid][j]=best.F;
    update(j,l,mid,L,best.S+1);
    update(j,mid+1,r,best.S,R);
}
long long take_photos(int n, int m, int k, vector<int> r, vector<int> c) {
    swap(n,m);
    fill(mx,mx+maxn,inf);
    for(ll i=0;i<m;i++){
	if(c[i]>r[i]){
	    swap(c[i],r[i]);
	}
	mx[r[i]]=min(mx[r[i]],(ll)c[i]);
    }
    for(ll i=0;i<n;i++){
	ff[i][0]=mx[i];
    }
    tt[1]=0;
    for(ll i=2;i<maxn;i++){
	tt[i]=tt[i/2]+1;
    }
    for(ll i=1;i<logg;i++){
	for(ll j=0;j<n;j++){
	    ll res=j+(1<<(i-1));
	    if(res>=n){
		ff[j][i]=ff[j][i-1];
	    }else{
		ff[j][i]=min(ff[j][i-1],ff[res][i-1]);
	    }
	}
    }
    imp.pb(0);
    for(ll i=1;i<=n;i++){
	if(mx[i-1]!=inf)imp.pb(i);
	dp[i][0]=inf;
    }	
    for(ll i=0;i<imp.size();i++){
	for(ll j=0;j<i;j++){
	    C[j][i]=cost(imp[i]-1,imp[j]-1);
	}
	for(ll j=i;j<imp.size();j++){
	    C[j][i]=inf;
	}
    }	
    for(ll j=1;j<=k;j++){
	update(j,0,imp.size(),0,imp.size());
    }
    return dp[imp.size()-1][k];
}

Compilation message (stderr)

aliens.cpp: In function 'long long int take_photos(int, int, int, std::vector<int>, std::vector<int>)':
aliens.cpp:90:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(ll i=0;i<imp.size();i++){
                ~^~~~~~~~~~~
aliens.cpp:94:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(ll j=i;j<imp.size();j++){
             ~^~~~~~~~~~~

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