You are given an array of strings equations that represent relationships between variables where each string equations[i] is of length 4 and takes one of two different forms: "xi==yi" or "xi!=yi".Here, xi and yi are lowercase letters (not necessarily different) that represent one-letter variable names.
Return true if it is possible to assign integers to variable names so as to satisfy all the given equations, or false otherwise.
Example 1:
Input: equations = ["a==b","b!=a"] Output: false Explanation: If we assign say, a = 1 and b = 1, then the first equation is satisfied, but not the second. There is no way to assign the variables to satisfy both equations.
Example 2:
Input: equations = ["b==a","a==b"] Output: true Explanation: We could assign a = 1 and b = 1 to satisfy both equations.
Example 3:
Input: equations = ["a==b","b==c","a==c"] Output: true
Example 4:
Input: equations = ["a==b","b!=c","c==a"] Output: false
Example 5:
Input: equations = ["c==c","b==d","x!=z"] Output: true
Constraints:
1 <= equations.length <= 500equations[i].length == 4equations[i][0]is a lowercase letter.equations[i][1]is either'='or'!'.equations[i][2]is'='.equations[i][3]is a lowercase letter.
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