我的代码中使用Perl的整数除法不起作用

Question

在下面的Perl程序中,由于某种原因,整数除法不会发生.相反,控制台输出两个整数的连接,也不会发生divsion的if语句.为什么是这样？谢谢.

码:

print "Please Enter Your First Number\n";
$num1 = <>; chomp $num1;

print "Please Enter Your Operation\n";
$operation = <>; chomp $operation;

print "Please Enter Your Second Number\n";
$num2 = <>; chomp $num2;

if ($operation == "+"){
    $result = $num1 + $num2;
} elsif ($operation == "-"){
    $result = $num1 - $num2;
} elsif ($operation == "*"){
    $result = $num1 * $num2;
#Problem HERE:
} elsif ($operation == "/"){
    if ($num2 == 0){
        print "Cant Divide be Zero Mate\n";
    } else {
        $result = $num1 / $num2;
    }
}

print "\n";
print "result of $num1 $operation $num2 = $result";

Answer 1

使用eq而不是==进行字符串比较.

print "Please Enter Your First Number\n";
$num1 = <>;
chomp $num1;

print "Please Enter Your Operation\n";
$operation = <>;
chomp $operation;

print "Please Enter Your Second Number\n";
$num2 = <>;
chomp $num2;

if ( $operation eq "+" ) {
    $result = $num1 + $num2;
}
elsif ( $operation eq "-" ) {
    $result = $num1 - $num2;
}
elsif ( $operation eq "*" ) {
    $result = $num1 * $num2;
}
elsif ( $operation eq "/" ) {
    if ( $num2 == 0 ) {
        print "Cant Divide be Zero Mate\n";
    }
    else {
        $result = $num1 / $num2;
    }
}

print "\n";
print "result of $num1 $operation $num2 = $result";

输出:

Please Enter Your First Number
6
Please Enter Your Operation
/
Please Enter Your Second Number
3

result of 6 / 3 = 2