Submission #1265074

#	Time	Username	Problem	Language	Result	Execution time	Memory
1265074		trandangquang	Collecting Stamps 3 (JOI20_ho_t3)	C++20	100 / 100	118 ms	171732 KiB

ho_t3

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

#define foru(i,a,b) for(int i=(a); i<=(b); ++i)
#define ford(i,a,b) for(int i=(a); i>=(b); --i)
#define rep(i,a) for(int i=0; i<(a); ++i)
#define bit(s,i) (((s)>>(i))&1)
#define all(a) (a).begin(),(a).end()
#define sz(a) (int)(a).size()
#define ii pair<int,int>
#define fi first
#define se second
#define int long long
#define eb emplace_back
#define pb push_back
#define ll long long
#define __builtin_popcount(a) __builtin_popcountll(a)

template <class X, class Y>
    bool maxi(X &x, Y y){
        if(x<y){
            x=y;
            return true;
        }
        return false;
    }

template <class X, class Y>
    bool mini(X &x, Y y){
        if(x>y){
            x=y;
            return true;
        }
        return false;
    }

const int N=222;

int n,L,x[N],t[N]; ll dp[N][N][N][2],f[N],s[N];

void solve(){
    cin>>n>>L;
    foru(i,1,n) cin>>x[i];
    foru(i,1,n) cin>>t[i];

    x[n+1]=L;
    foru(i,1,n) f[i]=f[i-1]+x[i]-x[i-1];
    ford(i,n,1) s[i]=s[i+1]+x[i+1]-x[i];

    memset(dp,0x3f,sizeof(dp));

    int res=0;

    dp[n+1][0][0][0]=dp[n+1][0][0][1]=0;
    ford(i,n+1,1) foru(j,0,n) foru(k,0,n) if(i>j){
        ll tim=dp[i][j][k][0],ntim=0;

        ntim=tim+x[i]-x[i-1];
        mini(dp[i-1][j][k+(ntim<=t[i-1])][0],ntim);
        ntim=tim+s[i]+f[j+1];
        mini(dp[i][j+1][k+(ntim<=t[j+1])][1],ntim);

        tim=dp[i][j][k][1];
        ntim=tim+x[j+1]-x[j];
        mini(dp[i][j+1][k+(ntim<=t[j+1])][1],ntim);
        ntim=tim+f[j]+s[i-1];
        mini(dp[i-1][j][k+(ntim<=t[i-1])][0],ntim);

        if(dp[i][j][k][0]<1e18) maxi(res,k);
        if(dp[i][j][k][1]<1e18) maxi(res,k);
    }

    cout<<res<<'\n';
}

int32_t main(){
    #define task "test"
    if(fopen(task".inp","r")){
        freopen(task".inp","r",stdin);
        freopen(task".out","w",stdout);
    }
    cin.tie(0)->sync_with_stdio(0);

    solve();
}

Compilation message (stderr)

ho_t3.cpp: In function 'int32_t main()':
ho_t3.cpp:79:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   79 |         freopen(task".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
ho_t3.cpp:80:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   80 |         freopen(task".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 75 / 75