题目要求
Given an array equations of strings that represent relationships between variables, each string equations[i]
has length 4
and takes one of two different forms: "a==b"
or "a!=b"
. Here, a
and b
are lowercase letters (not necessarily different) that represent one-letter variable names.
Return true
if and only if it is possible to assign integers to variable names so as to satisfy all the given equations.
Example 1:
Input: [“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: [“b==a”,”a==b”]
Output: true
Explanation: We could assign a = 1 and b = 1 to satisfy both equations.
Example 3:
Input: [“a==b”,”b==c”,”a==c”]
Output: true
Example 4:
Input: [“a==b”,”b!=c”,”c==a”]
Output: false
Example 5:
Input: [“c==c”,”b==d”,”x!=z”]
Output: true
Note:
1 <= equations.length <= 500
equations[i].length == 4
equations[i][0]
andequations[i][3]
are lowercase lettersequations[i][1]
is either'='
or'!'
equations[i][2]
is'='
题意解析
给出一个字符串数组,每个字符串的长度为4,中间两个字符为==
或者!=
,而第一个和最后一个为字母,代表一个数字。
判断这些等式是否都能满足。