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    copied!<p>I'm not sure if it's the best way to do it, but this could work (constraining shifts to be in the range 0-31.</p> <pre><code> public static void ShiftLeft(uint[] bitfield, int shift) { if(shift &lt; 0 || shift &gt; 31) { // handle error here return; } int len = bitfield.Length; int i = len - 1; uint prev = 0; while(i &gt;= 0) { uint tmp = bitfield[i]; bitfield[i] = bitfield[i] &lt;&lt; shift; if(i &lt; len - 1) { bitfield[i] |= (uint)(prev &amp; (1 &gt;&gt; shift) - 1 ) &gt;&gt; (32 - shift); } prev = tmp; i--; } } public static void ShiftRight(uint[] bitfield, int shift) { if(shift &lt; 0 || shift &gt; 31) { // handle error here return; } int len = bitfield.Length; int i = 0; uint prev = 0; while(i &lt; len) { uint tmp = bitfield[i]; bitfield[i] = bitfield[i] &gt;&gt; shift; if(i &gt; 0) { bitfield[i] |= (uint)(prev &amp; (1 &lt;&lt; shift) - 1 ) &lt;&lt; (32 - shift); } prev = tmp; i++; } } </code></pre> <p>PD: With this change, you should be able to handle shifts greater than 31 bits. Could be refactored to make it look a little less ugly, but in my tests, it works and it doesn't seem too bad performance-wise (unless, there's actually something built in to handle large bitsets, which could be the case).</p> <pre><code> public static void ShiftLeft(uint[] bitfield, int shift) { if(shift &lt; 0) { // error return; } int intsShift = shift &gt;&gt; 5; if(intsShift &gt; 0) { if(intsShift &gt; bitfield.Length) { // error return; } for(int j=0;j &lt; bitfield.Length;j++) { if(j &gt; intsShift + 1) { bitfield[j] = 0; } else { bitfield[j] = bitfield[j+intsShift]; } } BitSetUtils.ShiftLeft(bitfield,shift - intsShift * 32); return; } int len = bitfield.Length; int i = len - 1; uint prev = 0; while(i &gt;= 0) { uint tmp = bitfield[i]; bitfield[i] = bitfield[i] &lt;&lt; shift; if(i &lt; len - 1) { bitfield[i] |= (uint)(prev &amp; (1 &gt;&gt; shift) - 1 ) &gt;&gt; (32 - shift); } prev = tmp; i--; } } public static void ShiftRight(uint[] bitfield, int shift) { if(shift &lt; 0) { // error return; } int intsShift = shift &gt;&gt; 5; if(intsShift &gt; 0) { if(intsShift &gt; bitfield.Length) { // error return; } for(int j=bitfield.Length-1;j &gt;= 0;j--) { if(j &gt;= intsShift) { bitfield[j] = bitfield[j-intsShift]; } else { bitfield[j] = 0; } } BitSetUtils.ShiftRight(bitfield,shift - intsShift * 32); return; } int len = bitfield.Length; int i = 0; uint prev = 0; while(i &lt; len) { uint tmp = bitfield[i]; bitfield[i] = bitfield[i] &gt;&gt; shift; if(i &gt; 0) { bitfield[i] |= (uint)(prev &amp; (1 &lt;&lt; shift) - 1 ) &lt;&lt; (32 - shift); } prev = tmp; i++; } } </code></pre>
 

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