题目链接：点击打开链接

题意：

给定一个n

构造 一个n*n矩阵使得每行恰好有一个[0,n-1]且关于主对角线对称

且主对角线必须全为0

#include<stdio.h>
#include<iostream>
#include<string.h>
#include<set>
#include<vector>
#include<map>
#include<math.h>
#include<queue>
#include<string>
#include<stdlib.h>
#include<algorithm>
using namespace std;
#define N 1015
#define LL __int64
#define ll int
ll n;
ll mp[N][N];
ll a[N<<2];
int main(){
	ll i,j;
	while(~scanf("%d",&n)) {
		for(i=1;i<n;i++)a[i]=i;
		ll l = 1;
		for(i=1;i<=n-1;i++) {
			for(j=l;j<l+n-1;j++)
				mp[i][j-l+1] = a[j];
			l++;
			a[n+l-2] = a[l-1];
		}
		for(i=1;i<=n-1;i++) { 
			mp[i][n] = mp[i][i];
			mp[i][i] = 0;
		}
		for(i=1;i<=n-1;i++)mp[n][i] = mp[i][n];
		mp[n][n] = 0;
		for(i=1;i<=n;i++) 
			for(j=1;j<=n;j++)printf("%d%c",mp[i][j],j==n?'\n':' ');
	}
	return 0;
}