211 - 字符串置换

2017.9.28

这个String.replace 是正则替换的，看来是不能用了

public class Solution {
    /*
     * @param A: a string
     * @param B: a string
     * @return: a boolean
     */
	public static boolean Permutation(String A, String B) {
        // write your code here
		if(A.length() != B.length()){
			return false;
		}
		HashMap mapA = new HashMap<>();
		HashMap mapB = new HashMap<>();
		for(int i = 0; i < A.length(); i++){
			if(!mapA.containsKey(A.charAt(i))){
				mapA.put(A.charAt(i), 1);
			}
			else{
				mapA.put(A.charAt(i), mapA.get(A.charAt(i)) + 1);
			}
			
		}
		for(int i = 0; i < A.length(); i++){
			if(!mapB.containsKey(B.charAt(i))){
				mapB.put(B.charAt(i), 1);
			}
			else{
				mapB.put(B.charAt(i), mapB.get(B.charAt(i)) + 1);
			}
		}
		Iterator ite = mapA.keySet().iterator();
		while(ite.hasNext()){
			Character ch = (Character)ite.next();
			if(mapB.containsKey(ch) && mapA.get(ch)==mapB.get(ch)){
				ite.remove();
				mapB.remove(ch);
			}
			else{
				return false;
			}
		}
		if(!mapB.isEmpty()){
			return false;
		}
        return true;
    }
}