起初用slope得了65分，将斜率交叉相乘之后0分，求调

#include<iostream>
#include<cstring>
#include<algorithm>
#include<string>
#include<cstdio>
#include<cmath>
using namespace std;
const int maxn=4e6+5;
int n,m,f[maxn],q[maxn],num[maxn];
const double eps=1e-20;
int s[maxn],h,t;
inline int Y(int i){
	return f[i]+s[i];
}
inline int B(int i){
	return f[i]+s[i]-i*num[i];
}
inline int X(int i){
	return num[i];
}
inline double S(int x,int y){
	return 1.0*(Y(x)-Y(y))/(X(x)-X(y)-eps);
}

int main(){
	int T=0;
	cin>>n>>m;
	for(int i=1;i<=n;i++){
	    int ti;cin>>ti;
		T=max(T,ti);
		s[ti]+=ti;
		num[ti]++;
	}
	for(int i=1;i<=T+m;i++){
		num[i]+=num[i-1];
		s[i]+=s[i-1];
	}
	h=t=1;q[h]=0;
    for(int i=1;i<=T+m;i++){
    	while(h<t&&(Y(q[h])-Y(q[h+1])<=i*(X(q[h])-X(q[h+1])))) ++h;
    	f[i]=f[q[h]]+i*num[i]-i*num[q[h]]-s[i]+s[q[h]];
    	while(t>h&&(Y(q[t-1])-Y(q[t]))*(X(q[t])-X(i-m+1))>=(X(q[t-1])-X(q[t]))*(Y(q[t])-Y(i-m+1)))--t;
        if(i-m+1>0)q[++t]=i-m+1; 
	}int ans=0x7f7f7f7f;
	for(int i=T;i<=T+m;i++){
		ans=min(ans,f[i]);
	}
	cout<<ans;
	return 0;
}

65分代码如下

#include<iostream>
#include<cstring>
#include<algorithm>
#include<string>
#include<cstdio>
#include<cmath>
using namespace std;
const int maxn=4e6+5;
int n,m,f[maxn],q[maxn],num[maxn];
const double eps=1e-20;
int s[maxn],h,t;
inline int Y(int i){
	return f[i]+s[i];
}
inline int B(int i){
	return f[i]+s[i]-i*num[i];
}
inline int X(int i){
	return num[i];
}
inline double S(int x,int y){
	return 1.0*(Y(x)-Y(y))/(X(x)-X(y)-eps);
}
int main(){
	int T=0;
	cin>>n>>m;
	for(int i=1;i<=n;i++){
	    int ti;cin>>ti;
		T=max(T,ti);
		s[ti]+=ti;
		num[ti]++;
	}
	for(int i=1;i<=T+m;i++){
		num[i]+=num[i-1];
		s[i]+=s[i-1];
	}
	h=t=1;q[h]=0;
    for(int i=1;i<=T+m;i++){
    	while(h<t&&S(q[h],q[h+1])<=i) ++h;
    	f[i]=f[q[h]]+i*num[i]-i*num[q[h]]-s[i]+s[q[h]];
    	 while(t>h&&S(q[t-1],q[t])>=S(q[t],i-m+1))--t;
        if(i-m+1>0)q[++t]=i-m+1; 
	}int ans=0x7f7f7f7f;
	for(int i=T;i<=T+m;i++){
		ans=min(ans,f[i]);
	}
	cout<<ans;
	return 0;
}