952C - Ravioli Sort - CodeForces Solution

#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> pii;
double pi=3.1415926535897932384626433832795;
#define ll long long
#define pb push_back
#define ll1 unsigned long long
void yes() { cout << "YES\n"; }
void no() { cout << "NO\n"; }
void solve(){
    int n;
    cin >> n;
    bool flag = true;
    int a[n];
    for (int i = 0; i < n; ++i)
    {
        cin >> a[i];
    }
    for (int i = 1; i < n; ++i)
    {
        if (abs(a[i] - a[i - 1]) > 1){
            flag = false;
            break;
        }
    }
    if (flag) yes(); else no();
}
signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    ll t;
    //cin >> t;
    t=1;
    while (t  -->0){
        solve();
        cout << '\n';
    }
    return 0;
}