LeetCode-in-Go
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 * 104t.length == s.lengthsandtconsist of any valid ascii character.
Solution
func isIsomorphic(s string, t string) bool {
charMap := make([]int, 128)
str := []rune(s)
tar := []rune(t)
n := len(str)
for i := 0; i < n; i++ {
if charMap[tar[i]] == 0 {
if search(charMap, str[i], tar[i]) != -1 {
return false
}
charMap[tar[i]] = int(str[i])
} else {
if charMap[tar[i]] != int(str[i]) {
return false
}
}
}
return true
}
func search(charMap []int, tar rune, skip rune) int {
for i := 0; i < 128; i++ {
if i == int(skip) {
continue
}
if charMap[i] != 0 && charMap[i] == int(tar) {
return i
}
}
return -1
}