1.2 Check Permutation: Given two strings, write a method to decide if one is a permutation of the other.
There is one solution that is 0 (N log N) time. Another solution uses some space, but is O(N) time.
public boolean checkPermutation(String str1, String str2) {
//O(nlogn)
if (str1.length() != str2.length())
return false;
char[] a = str1.toCharArray();
char[] b = str2.toCharArray();
Arrays.sort(a);
Arrays.sort(b);
return Arrays.equals(a, b);
}
For O(n) method, use a hash table to check.
