AtCoder Beginner Contest 069 D - Grid Coloring

D - Grid Coloring

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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

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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.

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Sample Input 1

Copy

2 2
3
2 1 1

Sample Output 1

Copy

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.

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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

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Sample Input 3

Copy

1 1
1
1

Sample Output 3

Copy

1

       這次明明是一次很簡單的四連塊填進格子的問題。。然後因爲一開始的理解錯誤到最後都沒有寫出來，心疼自己，所以早上就來補題了。思路上沒有什麼難度，主要就是要實現一個‘ S ’形的方式進行儲存。

#include <cstdio>
#include <iostream>
using namespace std;
int pd[110][110];
int main(){
	int h,w,n,x=0;
	cin>>h>>w>>n;
	int a[n];
	for(int i=0;i<n;i++){
		cin>>a[i];
		for(int j=0;j<a[i];j++){
			if((x/w)%2==0) pd[x/w][x%w]=i+1;
			else pd[x/w][w-(x%w)-1]=i+1;
			x++;
		}
	}
	for(int i=0;i<h;i++){
		for(int j=0;j<w;j++){
			if(j==w-1) printf("%d\n",pd[i][j]);
			else printf("%d ",pd[i][j]);
		}
	}
	return 0;
}

雖然這次還是沒有做出來，可是爲了最後一題做Beginner好蠢，下次決定要開始做下個級別的了。