#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
#include<vector>
#include<queue>
#include<functional>
#include<utility>
#include<cassert>
using namespace std;
inline int read(){
    int x = 0,f = 1;
    char c = getchar();
    while(c < '0' || c > '9'){
        if(c == '-') f = -1;
        c = getchar();
    }
    while(c >= '0' && c <= '9'){
        x = (x << 3) + (x << 1) + (c ^ 48);
        c = getchar();
    }
    return x * f;
}
const int N = 2e3 + 11;
int n,p[N];
inline int find(int x){
    if(x == p[x]) return x;
    return p[x] = find(p[x]);
}
inline void merge(int x,int y){
    int xx = find(x),yy = find(y);
    if(xx == yy) return;
    p[yy] = xx;
}
inline int check(){
    int i,x = find(1);
    for(i = 2;i <= n + 1;i++){
        if(find(i) != x) return 0;
    }
    return 1;
}
int main(){
    int t,i,x,y;
    t = read();
    while(t--){
        n = read();
        for(i = 1;i <= n + 1;i++) p[i] = i;
        for(i = 1;i <= n;i++){
            x = read(),y = read();
            merge(x,y + 1);
        }
        printf("%d\n",check());
    }
    return 0;
}