BestCoder Round #27 D

最近看ML看的晕，各种数学不会，特么的最优化就算了还泛函数，能虐死你啊，还是刷刷bc补充点能量比较好

#pragma comment(linker, "/STACK:102400000,102400000")
#include<iostream>
#include<vector>
#include<algorithm>
#include<cstdio>
#include<queue>
#include<stack>
#include<string>
#include<map>
#include<set>
#include<cmath>
#include<cassert>
#include<cstring>
#include<iomanip>
#include<bitset>
using namespace std;
#define i64 long long
#define foreach(c,itr)  for(__typeof((c).begin()) itr=(c).begin();itr!=(c).end();itr++)
#define FOR(i,a,b)      for( int i = (a) ; i <= (b) ; i ++)
#define FF(i,a)         for( int i = 0 ; i < (a) ; i ++)
#define FFD(i,a,b)      for( int i = (a) ; i >= (b) ; i --)
#define S64(a)          scanf(in64,&a)
#define SS(a)           scanf("%d",&a)
#define LL(a)           ((a)<<1)
#define RR(a)           (((a)<<1)+1)
#define pb              push_back
#define pf              push_front
#define X               first
#define Y               second
#define CL(Q)           while(!Q.empty())Q.pop()
#define MM(name,what)   memset(name,what,sizeof(name))
#define MC(a,b)            memcpy(a,b,sizeof(b))
#define MAX(a,b)        ((a)>(b)?(a):(b))
#define MIN(a,b)        ((a)<(b)?(a):(b))
#define read            freopen("out.txt","r",stdin)
#define write            freopen("out2.txt","w",stdout)
#define lson l, m, rt << 1
#define rson m+1, r, rt << 1 | 1
#define MID ((l+r) >> 1)
#define lc rt << 1
#define rc rt << 1 | 1

const i64 inf64 = 0x2f3f3f3f3f3f3f3fLL;
const double oo = 10e9;
const double eps = 10e-9;
const double pi = acos(-1.0);
const int mod = 1000000007;
const int maxn = 101;

struct zz{
	int x;
	int y;
	int turn;
	const bool operator < (const zz & cmp) const{
		if (x != cmp.x){
			return x < cmp.x;
		}
		else{
			return y < cmp.y;
		}
	}
	const bool operator == (const zz & cmp) const{
		if (x == cmp.x && y == cmp.y) {
			return true;
		}
		else{
			return false;
		}
	}
}zx;

int n, m;
int f[maxn][maxn];
bool dp[maxn][maxn][2];

vector<zz>out[maxn][maxn];
int cnt[maxn][maxn];
vector<zz>in[maxn][maxn];
int Hash[maxn][maxn];

void bfs(){
	queue<zz>q;
	for (int x = 1; x <= n; x++){
		for (int y = 1; y <= n; y++){
			if (x < y){
				if (dp[x][y][0] == true){
					zx.x = x;
					zx.y = y;
					zx.turn = 0;
					q.push(zx);
				}
				if (cnt[x][y] == out[x][y].size()){
					dp[x][y][1] = true;
					zx.x = x;
					zx.y = y;
					zx.turn = 1;
					q.push(zx);
				}
			}
		}
	}
	zz now, to;
	while (!q.empty()){
		now = q.front();
		q.pop();
		if (now.turn == 0){
			for (int i = 0; i < in[now.x][now.y].size(); i++){
				to = in[now.x][now.y][i];
				cnt[to.x][to.y]--;
				if (cnt[to.x][to.y] == 0){
					dp[to.x][to.y][1] = true;
					to.turn = 1;
					q.push(to);
				}
			}
		}
		else{
			for (int i = 0; i < in[now.x][now.y].size(); i++){
				to = in[now.x][now.y][i];
				if (dp[to.x][to.y][0] == false){
					dp[to.x][to.y][0] = true;
					to.turn = 0;
					q.push(to);
				}
			}
		}
	}
}

bool start(){
	for (int i = 1; i <= n; i++){
		for (int j = 1; j <= n; j++){
			in[i][j].clear();
			out[i][j].clear();
			cnt[i][j] = 0;
			dp[i][j][0] = false;
			dp[i][j][1] = false;
			Hash[i][j] = 0;
		}
	}	
	
	for (int i = 1; i <= m; i++){
		for (int x = 1; x <= n; x++){
			for (int y = 1; y <= n; y++){
				if (x<y)
				if (f[i][x] == f[i][y]){
					dp[x][y][0] = true;
					dp[y][x][0] = true;
				}
			}
		}
	}
	zz now, to;

	int hashcnt = 0;
	for (now.x = 1; now.x <= n; now.x++){
		for (now.y = 1; now.y <= n; now.y++){
			if (now.x < now.y){
				hashcnt++;
				for (int i = 1; i <= m; i++){
					to.x = f[i][now.x];
					to.y = f[i][now.y];
					if (to.x > to.y){
						swap(to.x, to.y);
					}
					if (to.x != to.y){
						if (Hash[to.x][to.y] != hashcnt){
							Hash[to.x][to.y] = hashcnt;
							cnt[now.x][now.y]++;
							in[to.x][to.y].push_back(now);
						}
					}
				}
			}
		}
	}
	
	bfs();

	for (int x = 1; x <= n; x++){
		for (int y = 1; y <= n; y++){
			if (x < y){
				if (dp[x][y][0] == false){
					return false;
				}
			}
		}
	}
	return true;

}

int  main(){
	int T;
	cin >> T;
	while (T--){
		cin >> n >> m;
		for (int i = 1; i <= m; i++){
			for (int j = 1; j <= n; j++){
				//cin >> f[i][j];
				SS(f[i][j]);
			}
		}
		if (start()){
			printf("YES\n");
		}
		else{
			printf("NO\n");
		}
	}
	return 0;
}