Submission

Score: 100

User: SayRo

Problemset: ปริมาตรน้ำท่วม

Language: cpp

Time: 0.004 second

Submitted On: 2026-09-30 13:35:12

#include<bits/stdc++.h>
using namespace std;
#define ll long long
int main(){
    ll sum=0;
    int n;
    int arr[10001];
    cin>>n;
    for(int i=0;i<n;i++){
        cin>>arr[i];
    }
    int lo=1,hi=n-2,lm=arr[0],rm=arr[n-1];
    while(lo<=hi){
        if(lm<rm){
            sum+=max(0,lm-arr[lo]);
            lm=max(lm,arr[lo]);
            lo++;
        }
        else{
            sum+=max(0,rm-arr[hi]);
            rm=max(rm,arr[hi]);
            hi--;
        }
    }
    cout<<sum;
}