#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*/ scanf(char *, ...);
int /*<<< orphan*/ str_rev(int, char *);
int main() {
  char str[100];
  int n, i;
  scanf("%d\n", &n);
  for (i = 0; i < n - 1; i++) {
    scanf("%c", &str[i]);
  }
  str_rev(n, str);
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x80,%rsp
movl   $0x0,-0x4(%rbp)
lea    0xec7(%rip),%rdi
lea    -0x74(%rbp),%rsi
mov    $0x0,%al
call   1040 <scanf@plt>
movl   $0x0,-0x78(%rbp)
mov    -0x78(%rbp),%eax
mov    -0x74(%rbp),%ecx
sub    $0x1,%ecx
cmp    %ecx,%eax
jge    1183 <main+0x63>
movslq -0x78(%rbp),%rax
lea    -0x70(%rbp),%rsi
add    %rax,%rsi
lea    0xe96(%rip),%rdi
mov    $0x0,%al
call   1040 <scanf@plt>
mov    -0x78(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x78(%rbp)
jmp    114b <main+0x2b>
mov    -0x74(%rbp),%edi
lea    -0x70(%rbp),%rsi
call   1030 <str_rev@plt>
xor    %eax,%eax
add    $0x80,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %r14
push   %rbx
sub    $0x78,%rsp
lea    0xed2(%rip),%rdi
lea    0xc(%rsp),%rsi
xor    %eax,%eax
call   1040 <scanf@plt>
mov    0xc(%rsp),%edi
cmp    $0x2,%edi
jl     1174 <main+0x54>
lea    0xeba(%rip),%r14
xor    %ebx,%ebx
nopl   0x0(%rax)
lea    (%rsp,%rbx,1),%rsi
add    $0x10,%rsi
mov    %r14,%rdi
xor    %eax,%eax
call   1040 <scanf@plt>
add    $0x1,%rbx
movslq 0xc(%rsp),%rdi
lea    -0x1(%rdi),%rax
cmp    %rax,%rbx
jl     1150 <main+0x30>
lea    0x10(%rsp),%rsi
call   1030 <str_rev@plt>
xor    %eax,%eax
add    $0x78,%rsp
pop    %rbx
pop    %r14
ret

LLVM IR (-O0):
@.str = [4 x i8] c"%d\0A\00"
@.str.1 = [3 x i8] c"%c\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca [100 x i8]
%3 = alloca i32
%4 = alloca i32
store i32 0, i32* %1
%5 = call i32 (i8*, ...) @scanf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i32* %3)
store i32 0, i32* %4
br label %6
6: ; preds = %16, %0
%7 = load i32, i32* %4
%8 = load i32, i32* %3
%9 = sub nsw i32 %8, 1
%10 = icmp slt i32 %7, %9
br i1 %10, label %11, label %19
11: ; preds = %6
%12 = load i32, i32* %4
%13 = sext i32 %12 to i64
%14 = getelementptr inbounds [100 x i8], [100 x i8]* %2, i64 0, i64 %13
%15 = call i32 (i8*, ...) @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i8* %14)
br label %16
16: ; preds = %11
%17 = load i32, i32* %4
%18 = add nsw i32 %17, 1
store i32 %18, i32* %4
br label %6
19: ; preds = %6
%20 = load i32, i32* %3
%21 = getelementptr inbounds [100 x i8], [100 x i8]* %2, i64 0, i64 0
%22 = call i32 @str_rev(i32 %20, i8* %21)
ret i32 0
}

LLVM IR (-O2):
@.str = [4 x i8] c"%d\0A\00"
@.str.1 = [3 x i8] c"%c\00"
define i32 @main() {
%1 = alloca [100 x i8]
%2 = alloca i32
%3 = getelementptr inbounds [100 x i8], [100 x i8]* %1, i64 0, i64 0
%4 = bitcast i32* %2 to i8*
%5 = call i32 (i8*, ...) @scanf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i32* %2)
%6 = load i32, i32* %2
%7 = icmp sgt i32 %6, 1
br i1 %7, label %8, label %17
8: ; preds = %0, %8
%9 = phi i64 [ %12, %8 ], [ 0, %0 ]
%10 = getelementptr inbounds [100 x i8], [100 x i8]* %1, i64 0, i64 %9
%11 = call i32 (i8*, ...) @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i8* %10)
%12 = add nuw nsw i64 %9, 1
%13 = load i32, i32* %2
%14 = add nsw i32 %13, -1
%15 = sext i32 %14 to i64
%16 = icmp slt i64 %12, %15
br i1 %16, label %8, label %17
17: ; preds = %8, %0
%18 = phi i32 [ %6, %0 ], [ %13, %8 ]
%19 = call i32 @str_rev(i32 %18, i8* %3)
ret i32 0
}