https://vjudge.net/problem/Gym-100801J/origin

二分答案出最小距离，dpcheck，单调队列优化dp

#include <iostream>
#include <cstdio>
#include <queue>
#include <algorithm>
#include <cmath>
#include <cstring>
#define inf 2147483647
#define N 1000010
#define p(a) putchar(a)
#define For(i,a,b) for(long long i=a;i<=b;++i)

using namespace std;
long long n,T,l,r,mid,ans;
long long p[N],t[N],q[N],f[N];
void in(long long &x){
    long long y=1;char c=getchar();x=0;
    while(c<'0'||c>'9'){if(c=='-')y=-1;c=getchar();}
    while(c<='9'&&c>='0'){ x=(x<<1)+(x<<3)+c-'0';c=getchar();}
    x*=y;
}
void o(long long x){
    if(x<0){p('-');x=-x;}
    if(x>9)o(x/10);
    p(x%10+'0');
}

bool check(long long x){
    long long l=1,r=0;
    memset(q,0,sizeof(q));
    memset(f,0,sizeof(f));
    For(i,1,n){
        while(l<=r&&q[r]-q[l]>=x) l++;
        f[i]=f[q[l]]+t[i];
        while(l<=r&&f[q[r]]>=f[i]) r--;
        q[++r]=i;
    }
    if(f[n]+n-1<=T) return 1;
    else return 0;
}

signed main(){
    freopen("journey.in","r",stdin);
    freopen("journey.out","w",stdout);
    in(n);in(T);
    For(i,1,n-1) in(p[i]);
    For(i,2,n-1) in(t[i]);
    l=1;r=n;
    while(l<r){
        mid=(l+r)>>1;
        if(check(mid)) r=mid;
        else l=mid+1;
    }
    ans=p[l];
    For(i,l+1,n-1) ans=min(ans,p[i]);
    o(ans);
    return 0;
}