#define NULL ((void *)0)
typedef unsigned long size_t; // Customize by platform.
typedef long intptr_t;
typedef unsigned long uintptr_t;
typedef long scalar_t__; // Either arithmetic or pointer type.
/* By default, we understand bool (as a convenience). */
typedef int bool;
#define false 0
#define true 1

/* Forward declarations */

/* Type definitions */

/* Variables and functions */
int /*<<< orphan*/ printf(char *, int);
int /*<<< orphan*/ scanf(char *, int *, ...);
int main() {
  int n, x, y;
  scanf("%d", &n);
  while (n--) {
    scanf("%d %d", &x, &y);
    printf("%d cm2\n", x * y / 2);
  }
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
movl   $0x0,-0x4(%rbp)
lea    0xecd(%rip),%rdi
lea    -0x8(%rbp),%rsi
mov    $0x0,%al
call   1040 <scanf@plt>
mov    -0x8(%rbp),%eax
mov    %eax,%ecx
add    $0xffffffff,%ecx
mov    %ecx,-0x8(%rbp)
cmp    $0x0,%eax
je     118d <main+0x6d>
lea    0xea4(%rip),%rdi
lea    -0xc(%rbp),%rsi
lea    -0x10(%rbp),%rdx
mov    $0x0,%al
call   1040 <scanf@plt>
mov    -0xc(%rbp),%eax
imul   -0x10(%rbp),%eax
mov    $0x2,%ecx
cltd
idiv   %ecx
mov    %eax,%esi
lea    0xe83(%rip),%rdi
call   1030 <printf@plt>
jmp    1141 <main+0x21>
xor    %eax,%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %r15
push   %r14
push   %r12
push   %rbx
sub    $0x18,%rsp
lea    0xed1(%rip),%rdi
lea    0xc(%rsp),%rsi
xor    %eax,%eax
call   1040 <scanf@plt>
subl   $0x1,0xc(%rsp)
jb     1191 <main+0x71>
lea    0xeb4(%rip),%r14
lea    0x14(%rsp),%r15
lea    0x10(%rsp),%r12
lea    0xea9(%rip),%rbx
nopl   (%rax)
mov    %r14,%rdi
mov    %r15,%rsi
mov    %r12,%rdx
xor    %eax,%eax
call   1040 <scanf@plt>
mov    0x10(%rsp),%eax
imul   0x14(%rsp),%eax
mov    %eax,%esi
shr    $0x1f,%esi
add    %eax,%esi
sar    %esi
mov    %rbx,%rdi
call   1030 <printf@plt>
subl   $0x1,0xc(%rsp)
jae    1160 <main+0x40>
xor    %eax,%eax
add    $0x18,%rsp
pop    %rbx
pop    %r12
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [3 x i8] c"%d\00"
@.str.1 = [6 x i8] c"%d %d\00"
@.str.2 = [8 x i8] c"%d cm2\0A\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i32
%3 = alloca i32
%4 = alloca i32
store i32 0, i32* %1
%5 = call i32 (i8*, i32*, ...) @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0), i32* %2)
br label %6
6: ; preds = %10, %0
%7 = load i32, i32* %2
%8 = add nsw i32 %7, -1
store i32 %8, i32* %2
%9 = icmp ne i32 %7, 0
br i1 %9, label %10, label %17
10: ; preds = %6
%11 = call i32 (i8*, i32*, ...) @scanf(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.1, i64 0, i64 0), i32* %3, i32* %4)
%12 = load i32, i32* %3
%13 = load i32, i32* %4
%14 = mul nsw i32 %12, %13
%15 = sdiv i32 %14, 2
%16 = call i32 @printf(i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str.2, i64 0, i64 0), i32 %15)
br label %6
17: ; preds = %6
ret i32 0
}

LLVM IR (-O2):
@.str = [3 x i8] c"%d\00"
@.str.1 = [6 x i8] c"%d %d\00"
@.str.2 = [8 x i8] c"%d cm2\0A\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i32
%3 = alloca i32
%4 = bitcast i32* %1 to i8*
%5 = bitcast i32* %2 to i8*
%6 = bitcast i32* %3 to i8*
%7 = call i32 (i8*, i32*, ...) @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0), i32* %1)
%8 = load i32, i32* %1
%9 = add nsw i32 %8, -1
store i32 %9, i32* %1
%10 = icmp eq i32 %8, 0
br i1 %10, label %21, label %11
11: ; preds = %0, %11
%12 = call i32 (i8*, i32*, ...) @scanf(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.1, i64 0, i64 0), i32* %2, i32* %3)
%13 = load i32, i32* %2
%14 = load i32, i32* %3
%15 = mul nsw i32 %14, %13
%16 = sdiv i32 %15, 2
%17 = call i32 @printf(i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str.2, i64 0, i64 0), i32 %16)
%18 = load i32, i32* %1
%19 = add nsw i32 %18, -1
store i32 %19, i32* %1
%20 = icmp eq i32 %18, 0
br i1 %20, label %21, label %11
21: ; preds = %11, %0
ret i32 0
}