제출 #473810

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
473810		SaraMostafa	Sjekira (COCI20_sjekira)	C++14	0 / 110	27 ms	2596 KiB

sjekira

#include <bits/stdc++.h>
#include<unordered_map>
using namespace std;
#define ll long long
#define endl "\n"
#define Sara ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
const long long mod=1e9+7;
const double PI=acos(-1);
// 1 2 3 --> 1,2,3 ...1,2..1,3..1..2,3..2..3..none (2 power number of elements)
//1 2 3 --> 2--> 1,2..1,3..2,3..(!n/(r!(n-r)!)) aka:ncr
// 1 2 3 -->2-->1,2..2,1..1,3..3,1..2,3..3,2..(n!/(n-r)!) aka:npr
//1 2 3--> 1..1,2..1,2,3..2..2,3..3  number of subarrays -->(n*(n+1))/2 "sum of numbers from 1 to n."
/*
ll power(ll x,ll y)
{
    if(y==0)
        return 1;
    else if(y==1)
        return x%mod;
    ll  r=power(x%mod,((y%mod)/2)%mod);
    if(y%2==0)
        return ((r%mod)*(r%mod));
    else
        return ((r%mod)*(r%mod)*(x%mod));
}

ll inverse(ll md,ll x)
{
    return power(x%mod,mod-2);
}

*/

int main()
{
    //freopen("input.in","r",stdin);

    Sara
  int n;
  cin>>n;
  vector<ll>v(n);
  for(int i=0;i<n;i++) cin>>v[i];
  int m=n-1;
  while(m--){
    int a,b;
    cin>>a>>b;
  }
  ll sum=0;
  for(int i=n;i>=2;i--){
    sum+=(i+(i-1));
  }
  cout<<sum<<endl;

    return 0;
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 10
• Subtask 3: 0 / 30
• Subtask 4: 0 / 60