Binary Sequence

3.3

116 votes
Ad-Hoc, Easy, Getting Started, Number Theory, Python
Problem

Given four integers x,y,a and b. Determine if there exists a binary string having x 0's and y 1's such that the total number of subsequences equal to the sequence "01" in it is a and the total number of subsequences equal to the sequence "10" in it is b.

A binary string is a string made of the characters '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 (possibly, zero or all) elements.

Input Format

The first line contains a single integer T (1T105), denoting the number of test cases.

Each of the next T lines contains four integers x, y, a and b ((1x,y105, (0a,b109)), as described in the problem.

Output Format

For each test case, output "Yes'' (without quotes) if a string with given conditions exists and "No'' (without quotes) otherwise.

Time Limit: 2
Memory Limit: 256
Source Limit:
Explanation

When x, y, a and b are 3, 2, 4 and 2 respectively, string 00110 is a valid string. So answer is Yes

When x, y, a and b are 3, 3, 4 and 3 respectively, we can't find any valid string. So answer is No.

 

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