AtCoder Beginner Contest 069

C - 4-adjacent

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Time limit : 2sec / Memory limit : 256MB

Score : 400 points

Problem Statement

We have a sequence of length N, a=(a1,a2,…,aN). Each ai is a positive integer.

Snuke's objective is to permute the element in a so that the following condition is satisfied:

• For each 1≤i≤N−1, the product of ai and ai+1 is a multiple of 4.

Determine whether Snuke can achieve his objective.

Constraints

• 2≤N≤105
• ai is an integer.
• 1≤ai≤109

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Input

Input is given from Standard Input in the following format:

N
a1 a2 … aN

Output

If Snuke can achieve his objective, print Yes; otherwise, print No.

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Sample Input 1

3
1 10 100

Sample Output 1

Yes

One solution is (1,100,10).

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Sample Input 2

4
1 2 3 4

Sample Output 2

No

It is impossible to permute a so that the condition is satisfied.

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Sample Input 3

3
1 4 1

Sample Output 3

Yes

The condition is already satisfied initially.

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Sample Input 4

2
1 1

Sample Output 4

No

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Sample Input 5

6
2 7 1 8 2 8

Sample Output 5

Yes

#include<bits/stdc++.h>
using namespace std;
int n, t, f, z;
 
int main()
{
    t = 0; f = 0; z = 0;
    scanf("%d", &n);
    for(int i = 0; i < n; i++)
    {
        int a;
        scanf("%d", &a);
        if(a % 4 == 0) f++;
        else if(a % 2 == 0) t++;
        else z++;
    }
    int tmp = f - z;
    if(tmp >= 0) printf("Yes\n");
    else if(tmp == -1 && t == 0) printf("Yes\n");
    else printf("No\n");
    return 0;
}