#include<cstdio>
#include<vector>
#include<algorithm>
#define pb push_back
#define nxt (*it)
#define FOR(i,a,b)\
   for(int i=a; i<=b; ++i)
#define ALL(g)\
   for(typeof(g.begin()) it=g.begin(); it!=g.end(); ++it)
#define infile "zvon.in"
#define outfile "zvon.out"
#define nMax 100005
using namespace std;
 
vector < int > v[nMax];
 
int DP[nMax];
 
int N, M, T;
 
inline void init(){
    FOR(i,1,N){
        DP[i] = 0;
        v[i].clear();
    }
}
 
void read(){
    init();
 
    scanf("%d", &N);
 
    int x, y;
    FOR(i,1,N-1){
        scanf("%d %d", &x, &y);
 
        v[x].pb(y);
    }
}
 
bool cmp(const int &x, const int &y){
    return DP[x] > DP[y];
}
 
void DF(int x){
    ALL(v[x])
        DF(nxt);
 
    sort(v[x].begin(), v[x].end(), cmp);
 
    int step = 0;
    ALL(v[x])
        DP[x] = max(DP[x], DP[nxt] + (++ step));
}
 
int main(){
    freopen(infile, "r", stdin);
    freopen(outfile, "w", stdout);
 
    for(scanf("%d", &T); T; T--){
        read();
 
        DF(1);
 
        printf("%d\n", DP[1]);
    }
 
    fclose(stdin);
    fclose(stdout);
 
    return 0;
}