../images/Emo41.gif שתי חידות אלגוריתמים
1 ------------------------ Write a program (or explain how to do it) that will display a descending "spiral" of NxN numbers, using constant space (no arrays allowed). For example, here's what the spiral looks like for N=10: 99 98 97 96 95 94 93 92 91 90 64 63 62 61 60 59 58 57 56 89 65 36 35 34 33 32 31 30 55 88 66 37 16 15 14 13 12 29 54 87 67 38 17 4 3 2 11 28 53 86 68 39 18 5 0 1 10 27 52 85 69 40 19 6 7 8 9 26 51 84 70 41 20 21 22 23 24 25 50 83 71 42 43 44 45 46 47 48 49 82 72 73 74 75 76 77 78 79 80 81 2 ---------------------- Suppose you want to make a random 9 digit number, using every number from 1 to 9 exactly once. You have a process called random(top) that gives a random number up to top (if top was 5, it would give random numbers from 1 to 5) assume top couldn't be more than 9, how could you do this using random(top) only 9 times (or less)?
1 ------------------------ Write a program (or explain how to do it) that will display a descending "spiral" of NxN numbers, using constant space (no arrays allowed). For example, here's what the spiral looks like for N=10: 99 98 97 96 95 94 93 92 91 90 64 63 62 61 60 59 58 57 56 89 65 36 35 34 33 32 31 30 55 88 66 37 16 15 14 13 12 29 54 87 67 38 17 4 3 2 11 28 53 86 68 39 18 5 0 1 10 27 52 85 69 40 19 6 7 8 9 26 51 84 70 41 20 21 22 23 24 25 50 83 71 42 43 44 45 46 47 48 49 82 72 73 74 75 76 77 78 79 80 81 2 ---------------------- Suppose you want to make a random 9 digit number, using every number from 1 to 9 exactly once. You have a process called random(top) that gives a random number up to top (if top was 5, it would give random numbers from 1 to 5) assume top couldn't be more than 9, how could you do this using random(top) only 9 times (or less)?
