codeforces 418 C Square Table (随机算法)

​​http://codeforces.com/problemset/problem/418/C​​

While resting on the ship after the "Russian Code Cup" a boy named Misha invented an interesting game. He promised to give his quadrocopter to whoever will be the first one to make a rectangular table of size n × m, consisting of positive integers such that the sum of the squares of numbers for each row and each column was also a square.

Since checking the correctness of the table manually is difficult, Misha asks you to make each number in the table to not exceed 10⁸.

Input

The first line contains two integers n and m (1 ≤ n, m ≤ 100)  — the size of the table.

Output

Print the table that meets the condition: n lines containing m

Sample test(s)

Input

1 1

Output

1

Input

1 2

Output

3 4

special judge 构造类随机算法

构造形如：

a a a a b

a a a a b

---

a a a a b

的矩阵

d可以说是整个矩阵的X因素

#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstdlib>  //随机算法  rand
using namespace std;
bool OK(int a){
    int k=(int)sqrt(a);
    if(k*k==a)  return 1;
    return 0;
}
int main()
{
    int n,m;
    while(~scanf("%d%d",&n,&m)){
        int a,b,c,d;
        while(2>1){
            a=rand()%100+1;
            b=rand()%100+1;
            c=rand()%100+1;
            d=rand()%100+1;
            int s1=(m-1)*a*a+b*b;
            int s2=(n-1)*a*a+c*c;
            int s3=(m-1)*c*c+d*d;
            int s4=(n-1)*b*b+d*d;
            if(OK(s1)&&OK(s2)&&OK(s3)&&OK(s4)) break;
        }
        for(int i=0;i<n-1;i++){
            for(int j=0;j<m-1;j++) printf("%d ",a);
            printf("%d\n",b);
        }
        for(int j=0;j<m-1;j++) printf("%d ",c);
        printf("%d\n",d);
    }
    return 0;
}

后来和同学研究了一下，用四个for循环写也可以的（他过了）。