Submission #226465

#	Time	Username	Problem	Language	Result	Execution time	Memory
226465		thebes	Collecting Stamps 3 (JOI20_ho_t3)	C++14	100 / 100	236 ms	134988 KiB

ho_t3

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

typedef long long ll;
typedef pair<int,int> pii;

const int MN = 202;
int N, L, i, arr[MN], t[MN]; ll nxt, d, td, k, dis[2][MN][MN][MN];
struct idk{int l, r, k, p;};
bitset<MN> vs[2][MN][MN], st[2][MN][MN];
queue<idk> q;

int main(){
    for(scanf("%d%d",&N,&L),i=1;i<=N;i++)
        scanf("%d",&arr[i]);
    for(i=1;i<=N;i++)
        scanf("%d",&t[i]);
    arr[0]=0; t[0]=-1;
    q.push({0,0,0,0});
    memset(dis,0x3f,sizeof(dis));
    dis[0][0][0][0]=0;
    while(q.size()){
        idk cur=q.front(); q.pop();
        vs[cur.p][cur.l][cur.r][cur.k]=1;
        st[cur.p][cur.l][cur.r][cur.k]=0;
        ll T = dis[cur.p][cur.l][cur.r][cur.k];
        if((cur.r+1)%(N+1)==cur.l%(N+1)){
            continue; // cannot expand further
        }
        nxt=cur.r+1;
        if(nxt>N) nxt=0;
        d=arr[nxt]-arr[cur.r];
        if(d<0) d+=L;
        if(!cur.p) td=arr[cur.r]-arr[cur.l];
        else td=0;
        if(td<0) td+=L;
        d+=td;
        if(T+d<=t[nxt]) k=cur.k+1;
        else k=cur.k;
        if(T+d<dis[1][cur.l][nxt][k]){
            dis[1][cur.l][nxt][k]=T+d;
            if(!st[1][cur.l][nxt][k]){
                q.push({cur.l,nxt,k,1});
                st[1][cur.l][nxt][k]=1;
            }
        }
        nxt=cur.l-1;
        if(nxt<0) nxt=N;
        d=arr[cur.l]-arr[nxt];
        if(d<0) d+=L;
        if(cur.p) td=arr[cur.r]-arr[cur.l];
        else td=0;
        if(td<0) td+=L;
        d+=td;
        if(T+d<=t[nxt]) k=cur.k+1;
        else k=cur.k;
        if(T+d<dis[0][nxt][cur.r][k]){
            dis[0][nxt][cur.r][k]=T+d;
            if(!st[0][nxt][cur.r][k]){
                q.push({nxt,cur.r,k,0});
                st[0][nxt][cur.r][k]=1;
            }
        }
    }
    int ans=0;
    for(i=0;i<=N;i++){
        for(int j=0;j<=N;j++){
            for(int k=0;k<=N;k++){
                if(dis[0][i][j][k]<(1LL<<60)||dis[1][i][j][k]<(1LL<<60))
                    ans=max(ans,k);
            }
        }
    }
    printf("%d\n",ans);
    return 0;
}

Compilation message (stderr)

ho_t3.cpp: In function 'int main()':
ho_t3.cpp:43:39: warning: narrowing conversion of 'nxt' from 'll {aka long long int}' to 'int' inside { } [-Wnarrowing]
                 q.push({cur.l,nxt,k,1});
                                       ^
ho_t3.cpp:43:39: warning: narrowing conversion of 'k' from 'll {aka long long int}' to 'int' inside { } [-Wnarrowing]
ho_t3.cpp:60:39: warning: narrowing conversion of 'nxt' from 'll {aka long long int}' to 'int' inside { } [-Wnarrowing]
                 q.push({nxt,cur.r,k,0});
                                       ^
ho_t3.cpp:60:39: warning: narrowing conversion of 'k' from 'll {aka long long int}' to 'int' inside { } [-Wnarrowing]
ho_t3.cpp:14:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(scanf("%d%d",&N,&L),i=1;i<=N;i++)
         ~~~~~~~~~~~~~~~~~~~^~~~
ho_t3.cpp:15:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d",&arr[i]);
         ~~~~~^~~~~~~~~~~~~~
ho_t3.cpp:17:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d",&t[i]);
         ~~~~~^~~~~~~~~~~~

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