Welcome to the simulation of Shor's algorithm. There are four restrictions for Shor's algorithm: 1) The number to be factored (n) must be >= 15. 2) The number to be factored must be odd. 3) The number must not be prime. 4) The number must not be a prime power. There are efficient classical methods of factoring any of the above numbers, or determining that they are prime. Input the number you wish to factor. 15 Step 1 starting. Step 1 complete. Step 2 starting. Searching for q, the smallest power of 2 greater than or equal to n^2. Found q to be 256. Step 2 complete. Step 3 starting. Searching for x, a random integer coprime to n. Found x to be 13. Step 3 complete. Step 4 starting. Made register 1 with register size = 9 Created register 2 of size 4 Step 4 complete. Step 5 starting attempt: 1 Step 5 complete. Step 6 starting attempt: 1 Step 6 complete. Step 7 starting attempt: 1 Step 7 complete. Step 8 starting attempt: 1 Making progress in Fourier transform, 38.8235% done! Making progress in Fourier transform, 78.0392% done! Step 8 complete. Step 9 starting attempt: 1 Value of m measured as: 0 Step 9 complete. Measured, 0 this trial a failure! Steps 10 and 11 complete. Step 5 starting attempt: 2 Step 5 complete. Step 6 starting attempt: 2 Step 6 complete. Step 7 starting attempt: 2 Step 7 complete. Step 8 starting attempt: 2 Making progress in Fourier transform, 38.8235% done! Making progress in Fourier transform, 78.0392% done! Step 8 complete. Step 9 starting attempt: 2 Value of m measured as: 0 Step 9 complete. Measured, 0 this trial a failure! Steps 10 and 11 complete. Step 5 starting attempt: 3 Step 5 complete. Step 6 starting attempt: 3 Step 6 complete. Step 7 starting attempt: 3 Step 7 complete. Step 8 starting attempt: 3 Making progress in Fourier transform, 38.8235% done! Making progress in Fourier transform, 78.0392% done! Step 8 complete. Step 9 starting attempt: 3 Value of m measured as: 128 Step 9 complete. Steps 10 and 11 starting attempt: 3 Measured m: 128, rational approximation for m/q=0.5 is: 1 / 2 Candidate period is 2 13^1 + 1 mod 15 = 14, 13^1 - 1 mod 15 = 12 15 = 3 * 5 Steps 10 and 11 complete.