#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 /*<<< orphan*/ scanf(char *, int *);
int main() {
  int I, F;
  do {
    scanf("%d", &I);
    scanf("%d", &F);
  } while (I >= F);
  for (; I < F; I++, F--) {
    printf("%d %d ", I, F);
  }
  if (I == F) {
    printf("%d ", I);
  }
  printf("\nfim de programa\n");
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
movl   $0x0,-0x4(%rbp)
lea    0xeca(%rip),%rdi
lea    -0x8(%rbp),%rsi
call   1040 <scanf@plt>
lea    0xeba(%rip),%rdi
lea    -0xc(%rbp),%rsi
call   1040 <scanf@plt>
mov    -0x8(%rbp),%eax
cmp    -0xc(%rbp),%eax
jge    112f <main+0xf>
jmp    1160 <main+0x40>
mov    -0x8(%rbp),%eax
cmp    -0xc(%rbp),%eax
jge    1197 <main+0x77>
mov    -0x8(%rbp),%esi
mov    -0xc(%rbp),%edx
lea    0xe8a(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    -0x8(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x8(%rbp)
mov    -0xc(%rbp),%eax
add    $0xffffffff,%eax
mov    %eax,-0xc(%rbp)
jmp    1160 <main+0x40>
mov    -0x8(%rbp),%eax
cmp    -0xc(%rbp),%eax
jne    11b4 <main+0x94>
mov    -0x8(%rbp),%esi
lea    0xe59(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
lea    0xe4f(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    -0x4(%rbp),%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %r15
push   %r14
push   %rbx
sub    $0x10,%rsp
lea    0xec0(%rip),%rbx
lea    0xc(%rsp),%r14
lea    0x8(%rsp),%r15
nopw   0x0(%rax,%rax,1)
mov    %rbx,%rdi
mov    %r14,%rsi
call   1050 <scanf@plt>
mov    %rbx,%rdi
mov    %r15,%rsi
call   1050 <scanf@plt>
mov    0xc(%rsp),%esi
mov    0x8(%rsp),%edx
cmp    %edx,%esi
jge    1150 <main+0x20>
lea    0xe8a(%rip),%rbx
nopl   0x0(%rax)
mov    %rbx,%rdi
xor    %eax,%eax
call   1040 <printf@plt>
mov    0xc(%rsp),%esi
add    $0x1,%esi
mov    %esi,0xc(%rsp)
mov    0x8(%rsp),%edx
add    $0xffffffff,%edx
mov    %edx,0x8(%rsp)
cmp    %edx,%esi
jl     1180 <main+0x50>
jne    11b4 <main+0x84>
lea    0xe59(%rip),%rdi
xor    %eax,%eax
call   1040 <printf@plt>
lea    0xe4f(%rip),%rdi
call   1030 <puts@plt>
xor    %eax,%eax
add    $0x10,%rsp
pop    %rbx
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [3 x i8] c"%d\00"
@.str.1 = [7 x i8] c"%d %d \00"
@.str.2 = [4 x i8] c"%d \00"
@.str.3 = [18 x i8] c"\0Afim de programa\0A\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i32
%3 = alloca i32
store i32 0, i32* %1
br label %4
4: ; preds = %7, %0
%5 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0), i32* %2)
%6 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0), i32* %3)
br label %7
7: ; preds = %4
%8 = load i32, i32* %2
%9 = load i32, i32* %3
%10 = icmp sge i32 %8, %9
br i1 %10, label %4, label %11
11: ; preds = %7
br label %12
12: ; preds = %20, %11
%13 = load i32, i32* %2
%14 = load i32, i32* %3
%15 = icmp slt i32 %13, %14
br i1 %15, label %16, label %25
16: ; preds = %12
%17 = load i32, i32* %2
%18 = load i32, i32* %3
%19 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([7 x i8], [7 x i8]* @.str.1, i64 0, i64 0), i32 %17, i32 %18)
br label %20
20: ; preds = %16
%21 = load i32, i32* %2
%22 = add nsw i32 %21, 1
store i32 %22, i32* %2
%23 = load i32, i32* %3
%24 = add nsw i32 %23, -1
store i32 %24, i32* %3
br label %12
25: ; preds = %12
%26 = load i32, i32* %2
%27 = load i32, i32* %3
%28 = icmp eq i32 %26, %27
br i1 %28, label %29, label %32
29: ; preds = %25
%30 = load i32, i32* %2
%31 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0), i32 %30)
br label %32
32: ; preds = %29, %25
%33 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([18 x i8], [18 x i8]* @.str.3, i64 0, i64 0))
%34 = load i32, i32* %1
ret i32 %34
}

LLVM IR (-O2):
@.str = [3 x i8] c"%d\00"
@.str.1 = [7 x i8] c"%d %d \00"
@.str.2 = [4 x i8] c"%d \00"
@str = [17 x i8] c"\0Afim de programa\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i32
%3 = bitcast i32* %1 to i8*
%4 = bitcast i32* %2 to i8*
br label %5
5: ; preds = %5, %0
%6 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0), i32* %1)
%7 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0), i32* %2)
%8 = load i32, i32* %1
%9 = load i32, i32* %2
%10 = icmp slt i32 %8, %9
br i1 %10, label %11, label %5
11: ; preds = %5, %11
%12 = phi i32 [ %18, %11 ], [ %9, %5 ]
%13 = phi i32 [ %16, %11 ], [ %8, %5 ]
%14 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([7 x i8], [7 x i8]* @.str.1, i64 0, i64 0), i32 %13, i32 %12)
%15 = load i32, i32* %1
%16 = add nsw i32 %15, 1
store i32 %16, i32* %1
%17 = load i32, i32* %2
%18 = add nsw i32 %17, -1
store i32 %18, i32* %2
%19 = icmp slt i32 %16, %18
br i1 %19, label %11, label %20
20: ; preds = %11
%21 = icmp eq i32 %16, %18
br i1 %21, label %22, label %24
22: ; preds = %20
%23 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0), i32 %16)
br label %24
24: ; preds = %22, %20
%25 = call i32 @puts(i8* dereferenceable(1) getelementptr inbounds ([17 x i8], [17 x i8]* @str, i64 0, i64 0))
ret i32 0
}