#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 modular_pow(int, int, int);
int /*<<< orphan*/ printf(char *, int);
int /*<<< orphan*/ scanf(char *, int *, ...);
int main() {
  int t, x, a, b;
  scanf("%d", &t);
  while (t-- > 0) {
    scanf("%d %d", &a, &b);
    x = modular_pow(a, b, 10);
    printf("%d\n", x);
  }
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
movl   $0x0,-0x4(%rbp)
lea    0xebd(%rip),%rdi
lea    -0x8(%rbp),%rsi
mov    $0x0,%al
call   1050 <scanf@plt>
mov    -0x8(%rbp),%eax
mov    %eax,%ecx
add    $0xffffffff,%ecx
mov    %ecx,-0x8(%rbp)
cmp    $0x0,%eax
jle    11a2 <main+0x72>
lea    0xe94(%rip),%rdi
lea    -0x10(%rbp),%rsi
lea    -0x14(%rbp),%rdx
mov    $0x0,%al
call   1050 <scanf@plt>
mov    -0x10(%rbp),%edi
mov    -0x14(%rbp),%esi
mov    $0xa,%edx
call   1040 <modular_pow@plt>
mov    %eax,-0xc(%rbp)
mov    -0xc(%rbp),%esi
lea    0xe6e(%rip),%rdi
call   1030 <printf@plt>
jmp    1151 <main+0x21>
xor    %eax,%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %r15
push   %r14
push   %r12
push   %rbx
sub    $0x18,%rsp
lea    0xec1(%rip),%rdi
lea    0xc(%rsp),%rsi
xor    %eax,%eax
call   1050 <scanf@plt>
mov    0xc(%rsp),%eax
lea    -0x1(%rax),%ecx
mov    %ecx,0xc(%rsp)
test   %eax,%eax
jle    11bb <main+0x8b>
lea    0xe9c(%rip),%r14
lea    0x14(%rsp),%r15
lea    0x10(%rsp),%r12
lea    0xe91(%rip),%rbx
cs nopw 0x0(%rax,%rax,1)
nop
mov    %r14,%rdi
mov    %r15,%rsi
mov    %r12,%rdx
xor    %eax,%eax
call   1050 <scanf@plt>
mov    0x14(%rsp),%edi
mov    0x10(%rsp),%esi
mov    $0xa,%edx
call   1040 <modular_pow@plt>
mov    %rbx,%rdi
mov    %eax,%esi
call   1030 <printf@plt>
mov    0xc(%rsp),%eax
lea    -0x1(%rax),%ecx
mov    %ecx,0xc(%rsp)
test   %eax,%eax
jg     1180 <main+0x50>
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 = [4 x i8] c"%d\0A\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i32
%3 = alloca i32
%4 = alloca i32
%5 = alloca i32
store i32 0, i32* %1
%6 = call i32 (i8*, i32*, ...) @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0), i32* %2)
br label %7
7: ; preds = %11, %0
%8 = load i32, i32* %2
%9 = add nsw i32 %8, -1
store i32 %9, i32* %2
%10 = icmp sgt i32 %8, 0
br i1 %10, label %11, label %18
11: ; preds = %7
%12 = call i32 (i8*, i32*, ...) @scanf(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.1, i64 0, i64 0), i32* %4, i32* %5)
%13 = load i32, i32* %4
%14 = load i32, i32* %5
%15 = call i32 @modular_pow(i32 %13, i32 %14, i32 10)
store i32 %15, i32* %3
%16 = load i32, i32* %3
%17 = call i32 @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0), i32 %16)
br label %7
18: ; preds = %7
ret i32 0
}

LLVM IR (-O2):
@.str = [3 x i8] c"%d\00"
@.str.1 = [6 x i8] c"%d %d\00"
@.str.2 = [4 x i8] c"%d\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 sgt i32 %8, 0
br i1 %10, label %11, label %20
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 = call i32 @modular_pow(i32 %13, i32 %14, i32 10)
%16 = call i32 @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0), i32 %15)
%17 = load i32, i32* %1
%18 = add nsw i32 %17, -1
store i32 %18, i32* %1
%19 = icmp sgt i32 %17, 0
br i1 %19, label %11, label %20
20: ; preds = %11, %0
ret i32 0
}