Hacker earth Binary subsequence "01" and "10" Problem Solution:

Problem Statement: Given four number x, y, a and b check if there exists a binary string having x 0's and y 1's such that the total number of subsequence equal to the sequence "01" in it is a and the total number of subsequence equal to the sequence "10" in it is b. Given: A binary string is a string made of the character '0' and '1' only. A sequence a is a subsequence of a sequence b if a can be obtained from b by deletion of several element. 

Input Format

 The  first line contains a single integer T (1<=T<=10^5), denoting the number of test cases.

Each of the next T lines contains four integers x, y, a and b (1<=x, y<=10^5, 0<=a, b<=10^9)                            

Sample input:                                                                                                                          

3 

3 2 4 2  

3 3 6 3    

3 3 4 3 

Sample output    

   Yes

   Yes

    No                                                                                                             

Code:

t=int(input())

for i in range(t):

    x,y,a,b=(input()).split()

    if(int(x)*int(y)==int(a)+int(b)):

        print("Yes")

    else:

        print("No")

Screenshot of code and output: