HDU 多校 6400 Parentheses Matrix(构造)

// Problem: D. Parentheses Matrix
// Contest: Codeforces - 2018 Chinese Multi-University Training, Nanjing U Contest
// URL: https://codeforces.ml/gym/102192/problem/D
// Memory Limit: 128 MB
// Time Limit: 1000 ms
// Date: 2021-11-29 19:27:17
// --------by Herio--------#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull; 
const int N=1e3+5,M=2e4+5,inf=0x3f3f3f3f,mod=1e9+7;
const int hashmod[4] = {402653189,805306457,1610612741,998244353};
#define mst(a,b) memset(a,b,sizeof a)
#define PII pair<int,int>
#define PLL pair<ll,ll>
#define x first
#define y second
#define pb emplace_back
#define SZ(a) (int)a.size()
#define rep(i,a,b) for(int i=a;i<=b;++i)
#define per(i,a,b) for(int i=a;i>=b;--i)
#define IOS ios::sync_with_stdio(false),cin.tie(nullptr) 
void Print(int *a,int n){for(int i=1;i<n;i++)printf("%d ",a[i]);printf("%d\n",a[n]); 
}
template <typename T>		//x=max(x,y)  x=min(x,y)
void cmx(T &x,T y){if(x<y) x=y;
}
template <typename T>
void cmn(T &x,T y){if(x>y) x=y;
}
char a[N][N];
int main(){int t;cin>>t;while(t--){int n,m;cin>>n>>m;if( (n%2==1) && (m%2==1) ){rep(i,1,n){rep(j,1,m) putchar('(');putchar('\n');}continue;}else if( (m%2==1)  ){rep(i,1,n){if(i&1) rep(j,1,m) putchar('(');else rep(j,1,m) putchar(')');putchar('\n');}}else if( (n%2==1) ) {rep(i,1,n){rep(j,1,m) putchar(j&1?'(':')');putchar('\n');}			}else {bool rev = 0;if(n > m) swap(n,m),rev = true;if( n == 2){rep(i,1,m) a[1][i]='(',a[2][i]=')'; }else if(n==4){rep(i,1,n){rep(j,1,m/2) a[i][j]=i&1?'(':')';rep(j,m/2+1,m) a[i][j]=i<=n/2?'(':')';}}else {rep(i,1,n){rep(j,1,m){if(i==1||j==1) a[i][j]='(';else if(i==n||j==m) a[i][j]=')';else if((i+j)&1) a[i][j]='(';else a[i][j]=')';}}}if(rev){//printf("n=%d m=%d\n",n,m);rep(i,1,m){rep(j,1,n) putchar(a[j][i]);putchar('\n');}}else {//printf("n=%d m=%d\n",n,m);rep(i,1,n){rep(j,1,m) putchar(a[i][j]);putchar('\n');}}}}return 0;
}