p72 两个完全平方数的和(leetcode63)

class Solution {
public:
    bool judgeSquareSum(int c) 
    {
        int i = 0, j = (int)sqrt(c);

        while (i<=j)
        {
            long sum = (i * i + (long)(j * j));
            if (sum == c)
            {
                return true;
            }
            else if (sum < c)
            {
                i++;
            }
            else
            {
                j--;
            }
        }

        return false;
    }
};

class Solution {
        public boolean judgeSquareSum(int c)
        {
               int i=0,j=(int)Math.sqrt(c);
               
               while(i<=j)
               {
                   int sum=i*i+j*j;
                   if(sum==c)
                   {
                       return true;
                   }
                   else if(sum<c)
                   {
                       i++;
                   }
                   else
                   {
                       j--;
                   }
               }
               
               return false;
        }
    }