LeetCode [821] Shortest Distance to a Character

 821. Shortest Distance to a Character

Easy

Given a string S and a character C, return an array of integers representing the shortest distance from the character C in the string.

Example 1:

Input: S = "loveleetcode", C = 'e'
Output: [3, 2, 1, 0, 1, 0, 0, 1, 2, 2, 1, 0]

 

Note:

1. S string length is in [1, 10000].
2. C is a single character, and guaranteed to be in string S.
3. All letters in S and C are lowercase.

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class Solution { public int[] shortestToChar(String S, char C) { int len = S.length(); int[] ret = new int[len]; int e = -1; for(int i=0; i<len; ++i) { if(S.charAt(i)==C) e = i; if(e==-1) ret[i] = len; else ret[i] = i-e; } e = len; for(int i=len-1; i>=0; --i) { if(S.charAt(i)==C) e = i; if(e<len) ret[i] = Math.min(ret[i], e-i); } return ret; } }