package leetcode // 解法一 func firstUniqChar(s string) int { result := make([]int, 26) for i := 0; i < len(s); i++ { result[s[i]-'a']++ } for i := 0; i < len(s); i++ { if result[s[i]-'a'] == 1 { return i } } return -1 } // 解法二 // 执行用时: 8 ms // 内存消耗: 5.2 MB func firstUniqChar1(s string) int { charMap := make([][2]int, 26) for i := 0; i < 26; i++ { charMap[i][0] = -1 charMap[i][1] = -1 } for i := 0; i < len(s); i++ { if charMap[s[i]-'a'][0] == -1 { charMap[s[i]-'a'][0] = i } else { //已经出现过 charMap[s[i]-'a'][1] = i } } res := len(s) for i := 0; i < 26; i++ { //只出现了一次 if charMap[i][0] >= 0 && charMap[i][1] == -1 { if charMap[i][0] < res { res = charMap[i][0] } } } if res == len(s) { return -1 } return res }