Solution for sum of squeare numbers

Author: edyluisrey

src/leetcode/SumofSquareNumbers.java

@@ -0,0 +1,42 @@
+package leetcode;
+
+public class SumofSquareNumbers {
+
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+
+	}
+	
+	 public boolean judgeSquareSum(int c) {
+	        int limit = helper(c);
+	        int r =limit;
+	        for(int i=0; i<=limit && r>=i;){
+	            int sum =i*i + r*r;
+	            if(sum==c){
+	                return true;
+	            }else if(sum<c){
+	                i++;
+	            }else{
+	                r--;
+	            }
+	        }
+	        
+	        return false;
+	    }
+	    
+	    public int helper(int x){
+	        if(x<=1) return x;
+	        int start=0, end=x;
+	        while(start<=end) {
+	            int mid = start + (end-start)/2;
+	            if(x/mid==mid) 
+	                return mid;
+	            else if(x/mid<mid)
+	                end = mid-1;
+	            else
+	                start = mid+1;
+	        }
+	        return end; 
+	    }
+
+}