1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
#include<bits/stdc++.h>
using namespace std;
int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n,k,i,j,c;
    long long a=0;
    cin>>n>>k;
    vector<int>ile(n);
    for(i=0;i<n;++i){
        cin>>ile[i];
    }
    for(i=0;i<n-1;++i){
        if(ile[i]>ile[i+1]+k){a+=(ile[i]-ile[i+1]-k);ile[i+1]+=(ile[i]-ile[i+1]-k);}
        else if(ile[i]+k<ile[i+1]){j=i;c=ile[i+1]-k-ile[i];ile[i]+=c;a+=c;
            while(j>0 && ile[j]>ile[j-1]+k){
            a+=(ile[j]-k-ile[j-1]);ile[j-1]+=(ile[j]-k-ile[j-1]);--j;
            }
        }
    }
    cout<<a;
    return 0;
}