Submission #1838613

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Source Code Expand

#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<climits>
#include<iostream>
#include<string>
#include<stack>
#include<queue>
#include<vector>
#include<map>
#include<set>
#include<algorithm>
#include<numeric>

#define rep(n) for(int i=0;i<n;i++)
#define repp(j, n) for(int j=0;j<n;j++)
#define reppp(i, m, n) for(int i=m;i<=n;i++)
#define all(c) c.begin(), c.end()
#define rall(c) c.rbegin(), c.rend()
#define MOD 1000000007
#define MAX 1000000001
#define INF 1410065408
#define EPS 1e-9
#define DEBUG 0
#define ll long long
#define Pll pair<ll, ll>
#define Pii pair<int, int>
 
using namespace std;
struct edge{int from, to; ll cost;};

signed main(){
    int n;
    cin >> n;
    vector<int> a(n);
    rep(n)cin >> a[i];

    int x = 0, y = 0, j = 0;
    reppp(i, 1, n){
        if(i >= a[j]){
            j++;
        }else{
            x++;
        }
    }
    j = n-1;
    for(int i=n;i>=0;i--){
        if(i <= a[j]){
            j--;
        }else{
            y++;
        }
    }
    cout << min(x,y) << endl;
}

Submission Info

Judge Result