Submission #698064

#	Time	Username	Problem	Language	Result	Execution time	Memory
698064		myrcella	Collecting Stamps 3 (JOI20_ho_t3)	C++17	100 / 100	91 ms	86080 KiB

ho_t3

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

#define fi first
#define se second
#define pii pair<int,int>
#define pll pair<long long,long long>
#define pb push_back
#define debug(x) cerr<<#x<<"="<<x<<endl
#define pq priority_queue
#define inf 0x3f
#define rep(i,a,b) for (int i=a;i<(b);i++)
#define MP make_pair
#define SZ(x) (int(x.size()))
#define ll long long
#define mod 1000000007
#define ALL(x) x.begin(),x.end()
void inc(int &a,int b) {a=(a+b)%mod;}
void dec(int &a,int b) {a=(a-b+mod)%mod;}
void MIN(int &a,int b) {
	if (a==-1) a = b;
	else a = min(a,b);
}
int lowbit(int x) {return x&(-x);}
ll p0w(ll base,ll p) {ll ret=1;while(p>0){if (p%2ll==1ll) ret=ret*base%mod;base=base*base%mod;p/=2ll;}return ret;}

const int maxn = 222;
int n,len;
int pos[maxn];
int dp[maxn][maxn][maxn][2];
int t[maxn];
int big;
int ans = 0;

int main() {
//	freopen("input.txt","r",stdin);	
	std::ios::sync_with_stdio(false);cin.tie(0);
	memset(dp,-1,sizeof(dp));
	dp[0][0][0][0] = dp[0][0][0][1] = 0;
	cin>>n>>len;
	pos[0] = 0,pos[n+1] = len;
	rep(i,1,n+1) cin>>pos[i];
	rep(i,1,n+1) cin>>t[i];
	rep(i,0,n+1)
		rep(j,0,n-i+1)
			rep(k,0,i+j+1) {
//				cout<<i<<" "<<j<<" "<<k<<" "<<dp[i][j][k][0]<<" "<<dp[i][j][k][1]<<endl;
				if (dp[i][j][k][0]!=-1) {
					ans = max(ans,k);
					int tn = min(mod,dp[i][j][k][0] + pos[i+1]-pos[i]);
//					debug(tn);
					MIN(dp[i+1][j][k+(tn<=t[i+1])][0],tn);
					tn = min(mod,dp[i][j][k][0] + pos[i] + len-pos[n-j]);
//					debug(tn);
					MIN(dp[i][j+1][k+(tn<=t[n-j])][1],tn);
				}
				if (dp[i][j][k][1]!=-1) {
					ans = max(ans,k);
					int tn = min(mod,dp[i][j][k][1] + pos[n-j+1] - pos[n-j]);
//					debug(tn);
					MIN(dp[i][j+1][k+(tn<=t[n-j])][1],tn);
					tn = min(mod,dp[i][j][k][1] + len-pos[n-j+1] + pos[i+1]);
//					debug(tn);
					MIN(dp[i+1][j][k+(tn<=t[i+1])][0],tn);
				}
			}
	cout<<ans;
	return 0;
}

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