<?php
$point = 0;
switch (true) {
case $point >= 80:
echo 'A';
break;
case $point >= 70:
echo 'B';
break;
case $point >= 50:
echo 'C';
break;
case $point >= 30:
echo 'D';
break;
case $point >= 0:
echo 'E';
break;
default:
echo 'F';
break;
}
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