AtCoder Regular Contest 080 C ， D

C - 4-adjacent
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
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.

Sample Input 1
Copy
3
1 10 100
Sample Output 1
Copy
Yes
One solution is (1,100,10).

Sample Input 2
Copy
4
1 2 3 4
Sample Output 2
Copy
No
It is impossible to permute a so that the condition is satisfied.

Sample Input 3
Copy
3
1 4 1
Sample Output 3
Copy
Yes
The condition is already satisfied initially.

Sample Input 4
Copy
2
1 1
Sample Output 4
Copy
No
Sample Input 5
Copy
6
2 7 1 8 2 8
Sample Output 5
Copy
Yes

#include <bits/stdc++.h>using namespace std;int a[123456];int main(){    int n;    scanf("%d",&n);    int h=0,s=0,k=0;    for(int i=0;i<n;i++){        scanf("%d",&a[i]);        if(a[i]%4==0) h++;        else if(a[i]%2==0) s++;        else k++;    }    if(h>=k){        puts("Yes");    } else {        if(s==0){            if(h+1>=k){                puts("Yes");            } else {                puts("No");            }        } else {            n-=(2*h);            n-=s;            if(n>0){                puts("No");            } else {                puts("Yes");            }        }    }    return 0;}

D - Grid Coloring
Time limit : 2sec / Memory limit : 256MB

Score : 400 points

Problem Statement
We have a grid with H rows and W columns of squares. Snuke is painting these squares in colors 1, 2, …, N. Here, the following conditions should be satisfied:

For each i (1≤i≤N), there are exactly ai squares painted in Color i. Here, a1+a2+…+aN=HW.
For each i (1≤i≤N), the squares painted in Color i are 4-connected. That is, every square painted in Color i can be reached from every square painted in Color i by repeatedly traveling to a horizontally or vertically adjacent square painted in Color i.
Find a way to paint the squares so that the conditions are satisfied. It can be shown that a solution always exists.

Constraints
1≤H,W≤100
1≤N≤HW
ai≥1
a1+a2+…+aN=HW
Input
Input is given from Standard Input in the following format:

H W
N
a1 a2 … aN
Output
Print one way to paint the squares that satisfies the conditions. Output in the following format:

c11 … c1W
:
cH1 … cHW
Here, cij is the color of the square at the i-th row from the top and j-th column from the left.

Sample Input 1
Copy
2 2
3
2 1 1
Sample Output 1
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1 1
2 3
Below is an example of an invalid solution:

1 2
3 1
This is because the squares painted in Color 1 are not 4-connected.

Sample Input 2
Copy
3 5
5
1 2 3 4 5
Sample Output 2
Copy
1 4 4 4 3
2 5 4 5 3
2 5 5 5 3
Sample Input 3
Copy
1 1
1
1
Sample Output 3
Copy
1
Submit

#include <bits/stdc++.h>using namespace std;struct node{    int id;    int val;    bool operator < (const node& a) const{        return val<a.val;    }}a[100*100+100];int str[105][105];int main(){    int n,m;    cin>>n>>m;    int k;    cin>>k;    int h=0;    for(int i=1;i<=k;i++){        int g;        scanf("%d",&g);        a[h].id=i;        a[h].val=g;        h++;    }    sort(a,a+h);    h=0;    for(int i=1;i<=n;i++){        if(i%2){            for(int j=1;j<=m;j++){                str[i][j]=a[h].id;                a[h].val--;                if(a[h].val==0){                    h++;                }            }        } else {            for(int j=m;j>=1;j--){                str[i][j]=a[h].id;                a[h].val--;                if(a[h].val==0){                    h++;                }            }        }    }    for(int i=1;i<=n;i++){        for(int j=1;j<=m;j++){            printf("%d ",str[i][j]);        }        puts("");    }    return 0;}