Submission #1360820

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Source Code Expand

#include <cstdio>
#include <algorithm>
#include <iostream>
#include <vector>
#include <cstring>
#include <set>
#include <utility>
#include <cstdlib>
#include <cmath>
#include <queue>
#include <stack>
#include <string>
#include <map>
#include <cmath>
#include <deque>
#include <bitset>
#define ll long long
#define PI 3.1415926535897932384626433832795
#define read(x) scanf("%d",&x);
#define readll(x) cin>>x;
#define FOR(x,a,b) for(int x=a;x<b;x++)
#define MP make_pair
#define PB push_back
#define pii pair<int,int>
#define readN(N,X) for(int i=0;i<N;i++) cin>>X[i];
#define pff pair<double,double>
using namespace std;

int N;
int a[100005];


void No(){
	cout<<"No"<<endl;
	exit(0);
}

void Yes(){
	cout<<"Yes"<<endl;
	exit(0);
}

int main(){
   std::ios::sync_with_stdio(false); 
   cin>>N;
   FOR(i,0,N){
   		int x;
   		cin>>x;
   		a[x]++;
   		if (x == N || x == 0) No();
   }

   int ada=0;
   FOR(i,0,N){
   		if (a[i]) ada++;
   }
   if (ada > 2) No();

   if (a[N-1] == N) Yes();
   int wow = N-1;
   int L = 2;
   for (int i=2;i<=N;i++){
   		if ( a[wow] >= i && a[wow] <= L && a[wow-1] + a[wow] == N) Yes();
   		wow--;
   		L+=2;
   }
   No();
}

Submission Info

Judge Result