| … | |
… | |
| 126 | } |
126 | } |
| 127 | return (char *) s; |
127 | return (char *) s; |
| 128 | } |
128 | } |
| 129 | |
129 | |
| 130 | /* |
130 | /* |
| 131 | * Based on (n+1)^2 = n^2 + 2n + 1 |
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| 132 | * given that 1^2 = 1, then |
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| 133 | * 2^2 = 1 + (2 + 1) = 1 + 3 = 4 |
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| 134 | * 3^2 = 4 + (4 + 1) = 4 + 5 = 1 + 3 + 5 = 9 |
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| 135 | * 4^2 = 9 + (6 + 1) = 9 + 7 = 1 + 3 + 5 + 7 = 16 |
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| 136 | * ... |
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| 137 | * In other words, a square number can be express as the sum of the |
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| 138 | * series n^2 = 1 + 3 + ... + (2n-1) |
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| 139 | */ |
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| 140 | int |
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| 141 | isqrt (int n) |
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| 142 | { |
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| 143 | int result, sum, prev; |
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| 144 | |
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| 145 | result = 0; |
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| 146 | prev = sum = 1; |
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| 147 | while (sum <= n) |
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| 148 | { |
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| 149 | prev += 2; |
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| 150 | sum += prev; |
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| 151 | ++result; |
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| 152 | } |
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| 153 | return result; |
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| 154 | } |
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| 155 | |
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| 156 | /* |
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| 157 | * returns a char-pointer to a static array, in which a representation |
131 | * returns a char-pointer to a static array, in which a representation |
| 158 | * of the decimal number given will be stored. |
132 | * of the decimal number given will be stored. |
| 159 | */ |
133 | */ |
| 160 | char * |
134 | char * |
| 161 | ltostr10 (signed long n) |
135 | ltostr10 (signed long n) |
