# Enter your code here. Read input from STDIN. Print output to STDOUT

n = int(raw_input())
for each in range(n):
    m = int(raw_input())
    q = []
    for eachq in range(m):
        strcordinate = raw_input()
        cordinate = strcordinate.split(" ")
        q.append(cordinate)
    all_diff = {}
    for co in q:
        diff = int(co[0])-int(co[1])
        if diff <1:
            diff = diff *-1
        all_diff[co]= diff
    verify = {}
    for key, values in all_diff:
        if key, value in verify.keys():
            verify[value] = verify[value] +1
        else:
            
            verify[value] = 1
            
    
    d = dict((k, v) for k, v in verify.items() if v < 2)
    print d
    if d:
        length_of_d = len(d)
        print length_of_d, m
        
        if length_of_d > 1:
            print "NO"
        elif length_of_d == 1:
            if m %2 ==0:
                print "NO"
            else:
                d[0]
                print "YES"
        else:
            
            print "YES"