<p>Given a non-negative integer <code>c</code>, decide whether there&#39;re two integers <code>a</code> and <code>b</code> such that <code>a<sup>2</sup> + b<sup>2</sup> = c</code>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> c = 5
<strong>Output:</strong> true
<strong>Explanation:</strong> 1 * 1 + 2 * 2 = 5
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> c = 3
<strong>Output:</strong> false
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>0 &lt;= c &lt;= 2<sup>31</sup> - 1</code></li>
</ul>

class Solution {
public:
    bool judgeSquareSum(int c) {
        
        vector<int> v;
        
        long long x = 0;

        while (x * x <= INT_MAX) {
            v.push_back(int(x * x));
            x++;
        }

        int l = 0;
        int r = v.size() - 1;

        while (l <= r) {
            long long a = v[l];
            long long b = v[r];
            long long n = a + b;

            if (n == c) {
                return 1;
            } else if (n < c) {
                l++;
            } else {
                r--;
            }
        }

        return 0;
    }
};
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