#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*/ puts(char *);
int /*<<< orphan*/ scanf(char *, int *);
int main(void) {
  int snack;
  int students;
  int shortage;
  scanf("%d", &snack);
  scanf("%d", &students);
  shortage = snack % students;
  if (shortage == 0) {
    puts("0");
  } else {
    printf("%d\n", students - shortage);
  }
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
movl   $0x0,-0x4(%rbp)
lea    0xeba(%rip),%rdi
lea    -0x8(%rbp),%rsi
call   1050 <scanf@plt>
lea    0xeaa(%rip),%rdi
lea    -0xc(%rbp),%rsi
call   1050 <scanf@plt>
mov    -0x8(%rbp),%eax
cltd
idivl  -0xc(%rbp)
mov    %edx,-0x10(%rbp)
cmpl   $0x0,-0x10(%rbp)
jne    1184 <main+0x54>
lea    0xe89(%rip),%rdi
call   1030 <puts@plt>
jmp    1196 <main+0x66>
mov    -0xc(%rbp),%esi
sub    -0x10(%rbp),%esi
lea    0xe74(%rip),%rdi
call   1040 <printf@plt>
xor    %eax,%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbx
sub    $0x10,%rsp
lea    0xec4(%rip),%rbx
lea    0xc(%rsp),%rsi
mov    %rbx,%rdi
call   1050 <scanf@plt>
lea    0x8(%rsp),%rsi
mov    %rbx,%rdi
call   1050 <scanf@plt>
mov    0xc(%rsp),%eax
mov    0x8(%rsp),%esi
cltd
idiv   %esi
test   %edx,%edx
je     1175 <main+0x45>
sub    %edx,%esi
lea    0xe97(%rip),%rdi
call   1040 <printf@plt>
jmp    1181 <main+0x51>
lea    0xe87(%rip),%rdi
call   1030 <puts@plt>
xor    %eax,%eax
add    $0x10,%rsp
pop    %rbx
ret

LLVM IR (-O0):
@.str = [3 x i8] c"%d\00"
@.str.1 = [2 x i8] c"0\00"
@.str.2 = [4 x i8] c"%d\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 @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)
%7 = load i32, i32* %2
%8 = load i32, i32* %3
%9 = srem i32 %7, %8
store i32 %9, i32* %4
%10 = load i32, i32* %4
%11 = icmp eq i32 %10, 0
br i1 %11, label %12, label %14
12: ; preds = %0
%13 = call i32 @puts(i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.1, i64 0, i64 0))
br label %19
14: ; preds = %0
%15 = load i32, i32* %3
%16 = load i32, i32* %4
%17 = sub nsw i32 %15, %16
%18 = call i32 @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0), i32 %17)
br label %19
19: ; preds = %14, %12
ret i32 0
}

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