205. Isomorphic Strings

Easy
​
Given two strings s and t, determine if they are isomorphic.
Two strings s and t are isomorphic if the characters in s can be replaced to get t.
All occurrences of a character must be replaced with another character while preserving the order of characters. No two characters may map to the same character, but a character may map to itself.
Example 1:
Input: s = "egg", t = "add"
Output:
true
Example 2:
Input: s = "foo", t = "bar"
Output:
false
Example 3:
Input: s = "paper", t = "title"
Output:
true
Constraints:
  • 1 <= s.length <= 5 * 104
  • t.length == s.length
  • s and t consist of any valid ascii character.
​

解題

func isIsomorphic(s string, t string) bool {
m := make(map[byte]byte)
m2 := make(map[byte]byte)
for i:= range(s) {
if _,ok := m[s[i]]; ok {
if m[s[i]]!=t[i] {
return false
}
} else {
m[s[i]] = t[i]
}
}
for i:= range(t) {
if _,ok := m2[t[i]]; ok {
if m2[t[i]]!=s[i] {
return false
}
} else {
m2[t[i]] = s[i]
}
}
return true
}