#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*/ firstClassProb();
int /*<<< orphan*/ practice();
int /*<<< orphan*/ printf(char *);
int /*<<< orphan*/ scanf(char *, int *);
void main() {
  int choice;
  practice();
  do {
    printf("\nEnter Choice: ");
    scanf("%d", &choice);
    switch (choice) {
    case 1:
      firstClassProb();
      break;
    case 2:
      break;
    default:
      printf("\nError in Input");
      break;
    }
  } while (choice != 2);
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
mov    $0x0,%al
call   1060 <practice@plt>
lea    0xeaa(%rip),%rdi
call   1030 <printf@plt>
lea    0xeae(%rip),%rdi
lea    -0x4(%rbp),%rsi
call   1050 <scanf@plt>
mov    -0x4(%rbp),%eax
mov    %eax,-0x8(%rbp)
sub    $0x1,%eax
je     1190 <main+0x50>
jmp    117f <main+0x3f>
mov    -0x8(%rbp),%eax
sub    $0x2,%eax
je     119c <main+0x5c>
jmp    11a1 <main+0x61>
mov    $0x0,%al
call   1040 <firstClassProb@plt>
jmp    11ad <main+0x6d>
jmp    11ad <main+0x6d>
lea    0xe6b(%rip),%rdi
call   1030 <printf@plt>
jmp    11b2 <main+0x72>
cmpl   $0x2,-0x4(%rbp)
jne    114f <main+0xf>
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %r15
push   %r14
push   %r12
push   %rbx
push   %rax
xor    %eax,%eax
call   1060 <practice@plt>
lea    0xeaa(%rip),%r14
lea    0xeb3(%rip),%r15
lea    0x4(%rsp),%rbx
lea    0xeaa(%rip),%r12
jmp    117e <main+0x3e>
nopl   0x0(%rax,%rax,1)
xor    %eax,%eax
call   1040 <firstClassProb@plt>
cmpl   $0x2,0x4(%rsp)
je     11ae <main+0x6e>
mov    %r14,%rdi
call   1030 <printf@plt>
mov    %r15,%rdi
mov    %rbx,%rsi
call   1050 <scanf@plt>
mov    0x4(%rsp),%eax
cmp    $0x1,%eax
je     1170 <main+0x30>
cmp    $0x2,%eax
je     11ae <main+0x6e>
mov    %r12,%rdi
call   1030 <printf@plt>
cmpl   $0x2,0x4(%rsp)
jne    117e <main+0x3e>
add    $0x8,%rsp
pop    %rbx
pop    %r12
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [16 x i8] c"\0AEnter Choice: \00"
@.str.1 = [3 x i8] c"%d\00"
@.str.2 = [16 x i8] c"\0AError in Input\00"
define void @main() {
%1 = alloca i32
%2 = call i32 (...) @practice()
br label %3
3: ; preds = %13, %0
%4 = call i32 @printf(i8* getelementptr inbounds ([16 x i8], [16 x i8]* @.str, i64 0, i64 0))
%5 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i32* %1)
%6 = load i32, i32* %1
switch i32 %6, label %10 [
i32 1, label %7
i32 2, label %9
]
7: ; preds = %3
%8 = call i32 (...) @firstClassProb()
br label %12
9: ; preds = %3
br label %12
10: ; preds = %3
%11 = call i32 @printf(i8* getelementptr inbounds ([16 x i8], [16 x i8]* @.str.2, i64 0, i64 0))
br label %12
12: ; preds = %10, %9, %7
br label %13
13: ; preds = %12
%14 = load i32, i32* %1
%15 = icmp ne i32 %14, 2
br i1 %15, label %3, label %16
16: ; preds = %13
ret void
}

LLVM IR (-O2):
@.str = [16 x i8] c"\0AEnter Choice: \00"
@.str.1 = [3 x i8] c"%d\00"
@.str.2 = [16 x i8] c"\0AError in Input\00"
define void @main() {
%1 = alloca i32
%2 = bitcast i32* %1 to i8*
%3 = tail call i32 (...) @practice()
br label %4
4: ; preds = %12, %0
%5 = call i32 @printf(i8* dereferenceable(1) getelementptr inbounds ([16 x i8], [16 x i8]* @.str, i64 0, i64 0))
%6 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i32* %1)
%7 = load i32, i32* %1
switch i32 %7, label %10 [
i32 1, label %8
i32 2, label %15
]
8: ; preds = %4
%9 = call i32 (...) @firstClassProb()
br label %12
10: ; preds = %4
%11 = call i32 @printf(i8* dereferenceable(1) getelementptr inbounds ([16 x i8], [16 x i8]* @.str.2, i64 0, i64 0))
br label %12
12: ; preds = %8, %10
%13 = load i32, i32* %1
%14 = icmp eq i32 %13, 2
br i1 %14, label %15, label %4
15: ; preds = %4, %12
ret void
}