观光公交 贪心 思维

Code:

#include<cstdio>
#include<algorithm>
#include<string>
using namespace std;
void setIO(string a){ freopen((a+".in").c_str(),"r",stdin);}
void shutIO(){ fclose(stdin);}
#define maxn 1006
#define maxm 1000005
struct Node{
    int st, ed,t;
}e[maxm];
int sum[maxn],last[maxn],d[maxn],out[maxn],tim[maxn],range[maxn];   
int main(){
   // setIO("input");
    int n,m,k;
    scanf("%d%d%d",&n,&m,&k);
    for(int i=1;i<n;++i) scanf("%d",&d[i]);
    for(int i=1;i<=m;++i){
        scanf("%d%d%d",&e[i].t,&e[i].st,&e[i].ed);
        last[e[i].st]=max(last[e[i].st], e[i].t);                  
        out[e[i].ed]+=1;                                            
    }
    for(int i=1;i<n;++i) tim[i+1]=max(tim[i], last[i])+d[i];      
    long long ans=0;
    for(int i=1;i<=n;++i) sum[i]=sum[i-1]+out[i];                  
    for(int i=1;i<=m;++i) ans+=tim[e[i].ed]-e[i].t;                 
    while(k--){
        int flag=0,cur=0;
        range[n-1]=n;
        for(int i=n-2;i>=1;--i){
            if(tim[i+1]>last[i+1])  range[i]=range[i+1];
            else range[i]=i+1;
        }
        for(int i=1;i<=n;++i)
            if(sum[range[i]]-sum[i]>cur&&d[i]){
                cur=sum[range[i]]-sum[i];
                flag=i;
            }
        if(cur==0) break;
        ans-=cur;
        d[flag]-=1;
        tim[1]=0;
        for(int i=1;i<n;++i) tim[i+1]=max(tim[i],last[i])+d[i];
    }    
    printf("%lld\n",ans);
    shutIO();
    return 0;
}