/*

input:givenastring

output:2

input:howareyou

output:2

*/

package hash;

import java.util.HashMap;

public class FirstCharacter {

public static int firstUniqChar(String str) {

if (str == null || str.length() == 0) {

return 0;

}

HashMap<Character, Integer> dic = new HashMap<Character, Integer>();

char[] chars = str.toCharArray();

for (int i = 0; i < chars.length; i++) {

if (dic.containsKey(chars[i])) {

int newValue = dic.get(chars[i]) + 1;

dic.put(chars[i], newValue);

} else {

dic.put(chars[i], 1);

}

}

for (int i = 0; i < chars.length; i++) {

if (dic.get(chars[i]) == 1) {

return i;

}

}

return -1;

}

}