20 lines
480 B
PHP
20 lines
480 B
PHP
<?php
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function is_arithmetic($arr)
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{
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$delta = $arr[1] - $arr[0];
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for($index=0; $index<sizeof($arr)-1; $index++)
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{
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if (($arr[$index + 1] - $arr[$index]) != $delta)
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{
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return "Not an arithmetic sequence";
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}
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}
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return "A arithmetic sequence";
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}
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$my_arr1 = array(6, 7, 9, 11);
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$my_arr2 = array(5, 7, 9, 11);
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print_r(is_arithmetic($my_arr1)."\n");
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print_r(is_arithmetic($my_arr2)."\n");
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?>
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