#include<bits/stdc++.h> using namespace std; int t,n,m,ans; struct operation{ int idx1,to1,idx2,to2; }a[114514]; int mp[114514]; bool cmp(operation a,operation b){ if(a.idx1==b.idx1)return a.to1<b.to1; else if(a.idx1==b.idx2)return a.to1<b.to2; else if(a.idx2==b.idx1)return a.to2<b.to1; else if(a.idx2==b.idx2)return a.to2<b.to2; else if(a.to1!=b.to1) return a.to1<b.to1; else return a.to2<b.to2; } int main(){ freopen("max.in","r",stdin),freopen("max.out","w",stdout); scanf("%d",&t); while(t--){ memset(a,0,sizeof a),memset(mp,0,sizeof mp),scanf("%d%d",&n,&m),ans=0; for(int i=1;i<=m;i++)scanf("%d%d%d%d",&a[i].idx1,&a[i].to1,&a[i].idx2,&a[i].to2); sort(a+1,a+m+1,cmp); for(int i=1;i<=m;i++)mp[a[i].idx1]=a[i].to1,mp[a[i].idx2]=a[i].to2; for(int i=1;i<=n;i++)ans+=mp[i]; cout<<ans<<'\n'; } }