<p>Given two integers <code>left</code> and <code>right</code> that represent the range <code>[left, right]</code>, return <em>the bitwise AND of all numbers in this range, inclusive</em>.</p>

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

<pre>
<strong>Input:</strong> left = 5, right = 7
<strong>Output:</strong> 4
</pre>

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

<pre>
<strong>Input:</strong> left = 0, right = 0
<strong>Output:</strong> 0
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> left = 1, right = 2147483647
<strong>Output:</strong> 0
</pre>

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

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

class Solution {
public:
    int rangeBitwiseAnd(int left, int right) {
        long long rangeLen = 1ll*right - 1ll*left + 1, grpLen = 1, ans = 0;
        for(int i = 0; i < 32; i++) {
            if(rangeLen <= grpLen and (((left>>i) & 1) & ((right>>i) & 1))) ans = ans | (1 << i);
            grpLen = grpLen << 1;
        }
        return (int)ans;

    }
};
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