差分
#include<bits/stdc++.h>
using namespace std;
typedef long long int LL;
const int N=100000+10;
#define Mod 998244353
#define INF 1<<31-1
LL c2[N],c3[N];
LL ans2[N],ans3[N];
LL quick_power(LL a,LL b)
{
LL ans=1;
a = a%Mod;
while(b>0)
{
if(b%2 == 1)
ans =ans*a%Mod;
b =b/2;
a =a*a% Mod;
}
return ans%Mod;
}
LL min1(LL a,LL b)
{
if(a>b)
return b;
else
return a;
}
int main()
{
int t;
scanf("%d",&t);
while(t--)
{
LL n,m;
scanf("%lld%lld",&n,&m);
for(int i=1;i<=n+9;i++)
{
c2[i]=0;
c3[i]=0;
ans2[i]=0;
ans3[i]=0;
}
LL l,r,q;
for(int i=1;i<=m;i++)
{
scanf("%lld%lld%lld",&l,&r,&q);
if(q==2)
{
c2[l]++;
c2[r+1]--;
}
else
{
c3[l]++;
c3[r+1]--;
}
}
for(int i=1;i<=n;i++)
{
ans2[i]=ans2[i-1]+c2[i];
ans3[i]=ans3[i-1]+c3[i];
}
/* for(int i=1;i<=n;i++)
{
printf("%d ",ans2[i]);
}
cout<<endl;
for(int i=1;i<=n;i++)
{
printf("%d ",ans3[i]);
}
cout<<endl;*/
LL x=0,y=0,mi2=INF,mi3=INF;
for(int i=1;i<=n;i++)
{
mi2=min(mi2,ans2[i]);
mi3=min(mi3,ans3[i]);
}
// printf("%d\n",x);
LL sum=((quick_power(2,mi2)%Mod)*(quick_power(3,mi3)%Mod))%Mod;
printf("%lld\n",sum);
}
return 0;
}