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#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<algorithm>
#include<stack>
#include<map>
#include<set>
#include<vector>
#include<queue>
#include<string>
#include<cmath>
using namespace std;
#define ll long long
#define rep(i,n) for(int i =0; i < n; ++i)
#define CLR(x) memset(x,0,sizeof x)
#define MEM(a,b) memset(a,b,sizeof a)
#define pr(x) cout << #x << " = " << x << " ";
#define prln(x) cout << #x << " = " << x << endl;
const int maxn = 4e5+100;
const int INF = 0x3f3f3f3f;
int l[maxn], r[maxn];
int edgenum, head[maxn], to[maxn], nxt[maxn];
void addedge(int u, int v) {
nxt[edgenum] = head[u];
to[edgenum] = v;
head[u] = edgenum++;
}
bool vis[maxn];
void bfs(int s) {
queue<int> q;
q.push(s);
while(q.size()){
int u = q.front();
q.pop();
vis[u] = true;
for(int i = head[u]; ~i; i = nxt[i]) {
int v = to[i];
if(vis[v]) continue;
q.push(v);
}
}
}
int main(){
#ifdef LOCAL
freopen("/home/zeroxf/桌面/in.txt","r",stdin);
#endif
int t, n, m;
scanf("%d", &t);
while(t--){
scanf("%d%d", &n, &m);
MEM(l,0);MEM(r,0);
MEM(vis,0);
MEM(head,-1);
edgenum = 0;
int a, b;
for(int i = 0; i < m; ++i){
scanf("%d%d", &a, &b);
l[a]++;r[b]++;
addedge(a,b);
addedge(b,a);
}
bfs(1);
bool ok = true, ok2 = true;
for(int i = 1; i <= n; ++i){
if(!vis[i]) ok = false;
}
a = 0, b = 0;
for(int i = 1; i <= n; ++i){
if((l[i]+r[i])%2) b++;
if(l[i] == r[i]) continue;
if(abs(l[i]-r[i]) == 1) a++;
else ok2 = false;
}
if(ok&&b<3) printf("Yes ");
else printf("No ");
if(ok&&ok2&&a<3) printf("Yes\n");
else printf("No\n");
}
return 0;
}
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