38 lines
611 B
PHP
38 lines
611 B
PHP
<?php
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$days_in_month = array(
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1 => 31,
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2 => 28,
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3 => 31,
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4 => 30,
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5 => 31,
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6 => 30,
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7 => 31,
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8 => 31,
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9 => 30,
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10 => 31,
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11 => 30,
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12 => 31
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);
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$day_cycle = 0;
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for($year=1900; $year <= 2000; $year++) {
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for($month=1; $month <= 12; $month++) {
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$cdates = $days_in_month[$month];
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if($month == 2) {
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if($year % 4 == 0) {
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$cdates = 29;
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}
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if($years % 100 == 0) {
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$cdates = 28;
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}
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if($years % 400 == 0) {
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$cdates = 29;
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}
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}
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$day_cycle += $cdates;
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if($day_cycle % 7 == 0) {
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if($year >= 1901) {$sum++; }
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}
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}
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}
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echo $sum; |