Floyd's triangle: Difference between revisions
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# Write a program to generate and display here the first n lines of a Floyd triangle.<br>(Use n=5 and n=15 rows). |
# Write a program to generate and display here the first n lines of a Floyd triangle.<br>(Use n=5 and n=15 rows). |
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# Ensure that when displayed in a monospace font, the numbers line up in vertical columns as shown and that only one space separates the two largest numbers. |
# Ensure that when displayed in a monospace font, the numbers line up in vertical columns as shown and that only one space separates the two largest numbers. |
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=={{header|Go}}== |
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<lang go>package main |
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import "fmt" |
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func main() { |
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floyd(5) |
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floyd(15) |
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} |
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func floyd(n int) { |
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fmt.Printf("Floyd %d:\n", n) |
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w := len(fmt.Sprint(n * (n + 1) / 2)) |
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for i, row, last := 1, 1, 1; row <= n; i++ { |
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fmt.Printf("%*d", w, i) |
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if i == last { |
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row++ |
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last += row |
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fmt.Println() |
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} else { |
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fmt.Print(" ") |
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} |
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} |
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}</lang> |
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{{out}} |
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<pre> |
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Floyd 5: |
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1 |
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2 3 |
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4 5 6 |
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7 8 9 10 |
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11 12 13 14 15 |
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Floyd 15: |
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1 |
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2 3 |
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4 5 6 |
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7 8 9 10 |
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11 12 13 14 15 |
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16 17 18 19 20 21 |
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22 23 24 25 26 27 28 |
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29 30 31 32 33 34 35 36 |
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37 38 39 40 41 42 43 44 45 |
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46 47 48 49 50 51 52 53 54 55 |
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56 57 58 59 60 61 62 63 64 65 66 |
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67 68 69 70 71 72 73 74 75 76 77 78 |
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79 80 81 82 83 84 85 86 87 88 89 90 91 |
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92 93 94 95 96 97 98 99 100 101 102 103 104 105 |
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106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 |
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</pre> |
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=={{header|Python}}== |
=={{header|Python}}== |
Revision as of 23:15, 24 June 2012
Floyd's triangle lists the natural numbers in a right triangle aligned to the left where
- the first row is just 1
- successive rows start towards the left with the next number followed by successive naturals listing one more number than the line above.
The first few lines of a Floyd triangle looks like this:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
The task is to:
- Write a program to generate and display here the first n lines of a Floyd triangle.
(Use n=5 and n=15 rows). - Ensure that when displayed in a monospace font, the numbers line up in vertical columns as shown and that only one space separates the two largest numbers.
Go
<lang go>package main
import "fmt"
func main() {
floyd(5) floyd(15)
}
func floyd(n int) {
fmt.Printf("Floyd %d:\n", n) w := len(fmt.Sprint(n * (n + 1) / 2)) for i, row, last := 1, 1, 1; row <= n; i++ { fmt.Printf("%*d", w, i) if i == last { row++ last += row fmt.Println() } else { fmt.Print(" ") } }
}</lang>
- Output:
Floyd 5: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Floyd 15: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120
Python
<lang python>>>> def floyd(rowcount=5): rows = 1 while len(rows) < rowcount: n = rows[-1][-1] + 1 rows.append(list(range(n, n + len(rows[-1]) + 1))) return rows
>>> floyd() [[1], [2, 3], [4, 5, 6], [7, 8, 9, 10], [11, 12, 13, 14, 15]] >>> def pfloyd(rows=[[1], [2, 3], [4, 5, 6], [7, 8, 9, 10]]): colspace = [len(str(n)) for n in rows[-1]] for row in rows: print( ' '.join('%*i' % space_n for space_n in zip(colspace, row)))
>>> pfloyd()
1
2 3
4 5 6
7 8 9 10
>>> pfloyd(floyd(8))
1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 >>> pfloyd(floyd(15))
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105
106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 >>> </lang>