tp1

tp/tp1/aide.md

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+### Setting a bit
+
+Use the bitwise OR operator (|) to set a bit.
+
+`number |= 1 << x;`
+
+That will set bit x.
+
+### Clearing a bit
+
+Use the bitwise AND operator (&) to clear a bit.
+
+`number &= ~(1 << x);`
+
+That will clear bit x. You must invert the bit string with the bitwise NOT operator (~), then AND it.
+
+### Toggling a bit
+
+The XOR operator (^) can be used to toggle a bit.
+
+`number ^= 1 << x;`
+
+That will toggle bit x.
+
+### Checking a bit
+
+You didn't ask for this but I might as well add it.
+
+To check a bit, shift the number x to the right, then bitwise AND it:
+
+`bit = (number >> x) & 1;`
+
+That will put the value of bit x into the variable bit.
+
+### Changing the nth bit to x
+
+Setting the nth bit to either 1 or 0 can be achieved with the following:
+
+`number ^= (-x ^ number) & (1 << n);`
+
+Bit n will be set if x is 1, and cleared if x is 0.