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    <p>Computers are binary devices. Because of this, numbers are represented by a sequence of 1s and 0s.</p> <p>Bitshifting is simply moving those sequences of 1s and 0s left or right.</p> <p>So all the <code>&gt;&gt;</code> operator does is shift the bits towards the right one bit.</p> <p>Consider the number 101:</p> <pre><code>// Assuming signed 8-bit integers 01100101 // How 101 is represented in binary 00110010 // After right shifting one bit, this represents 50 </code></pre> <p>The least significant bit in this case was truncated. Obviously the devil's in the details, but that's all there is really to it.</p> <p>The <code>&lt;&lt;</code> operator does the opposite operation:</p> <pre><code>// Assuming signed 8-bit integers 01100101 // How 101 is represented in binary 11001010 // After left shifting one bit, this represents -54 // Assuming unsigned 8-bit integers 01100101 // How 101 is represented in binary 11001010 // After left shifting one bit, this represents 202 </code></pre> <p>In this case, the most significant bit was truncated since I used only 8-bits. If the number had more bits, however:</p> <pre><code>// Assuming signed 16-bit integers 00000000 01100101 // How 101 is represented in binary 00000000 11001010 // After left shifting one bit, this represents 202 00000001 10010100 // After left shifting one bit again, this represents 404 </code></pre> <p>So you may get different numbers depending on how many bits and the data types associated with those bits you're dealing with.</p> <p><strong>Addendum:</strong> If you're wondering how binary works, think about how the decimal number system works. Consider the number 5287. It can be written like this:</p> <pre><code>5287 </code></pre> <p>But you can also write it out like this:</p> <pre><code>5287 = (5 * 1000) + (2 * 100) + (8 * 10) + (7 * 1) </code></pre> <p>Which you can then write out like this:</p> <pre><code>5287 = (5 * 10^3) + (2 * 10^2) + (8 * 10^1) + (7 * 10^0) </code></pre> <p>The above equation explains why the decimal number system is sometimes called the base-10 system. The decimal number system employs the use of 10 digits (0-9). Notice how the exponents correspond to digit position.</p> <p>The binary number system, or the base-2 system, is the exact same thing but with the number two as the base of the exponents, and employing only two digits: 0 and 1.</p> <pre><code>5287 = 00010100 10100111 (base 2) = (0 * 2^15) + (0 * 2^14) + (0 * 2^13) + (1 * 2^12) + (0 * 2^11) + (1 * 2^10) + (0 * 2^9) + (0 * 2^8) + (1 * 2^7) + (0 * 2^6) + (1 * 2^5) + (0 * 2^4) + (0 * 2^3) + (1 * 2^2) + (1 * 2^1) + (1 * 2^0) </code></pre>
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    1. POWhat does >> do in java?
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    1. USIn silico
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    1. POWhat does >> do in java?
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    1. COPractically, it divides by two, and the other one multiplies by two.
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      1. USJoeri Hendrickx
    2. CO@Joeri Hendrickx: For integers, `>>` is in fact the same as dividing by two (which way it rounds depends on exact format) and `<<` is in fact the same as multiplying by two. It's a useful "trick" if you need to multiply/divide by two on processors that don't have multiply/divide instructions. Remember, this trick only works on integers. Attempting this trick on floating point numbers results in garbage.
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