<?php
$point = 0;
if ($point >= 80) {
echo 'A';
} elseif ($point >= 70) {
echo 'B';
} elseif ($point >= 50) {
echo 'C';
} elseif ($point >= 30) {
echo 'D';
} elseif ($point >= 0) {
echo 'E';
} else {
echo 'F';
}
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