Isomorphic Strings Check

You are given two strings s₁ and s₂. Your task is to determine whether the two strings are isomorphic. Two strings are isomorphic if there is a one-to-one mapping between every character of s₁ and every character of s₂.

Formally, there exists a bijection f: Σ → Σ such that for every index i,
\( f(s_{1}[i]) = s_{2}[i] \).

Note: The empty strings are isomorphic.

inputFormat

The input is read from stdin as follows:

• The first line contains an integer T, the number of test cases.
• Then, for each test case, there are two lines: the first line contains the string s₁ and the second line contains the string s₂. These strings may be empty.

outputFormat

For each test case, output a single line to stdout containing Yes if the two strings are isomorphic, otherwise output No.

## sample

3
egg
add
foo
bar
paper
title

Yes
No
Yes

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