x86asm-nasm, 399 bytes

Result

WA

Duration

596ms

Code [DL]

section .data  
section .text  
global main    
               
main:          
mov ebp, esp   
sub esp, 32    
               
mov edx, 2     
mov ecx, esp   
mov ebx, 0     
mov eax, 3     
int 0x80       
               
mov eax, [esp] 
add eax, 1     
mov [esp], eax 
               
mov edx, 1     
mov ecx, esp   
mov ebx, 1     
mov eax, 4     
int 0x80       
               
add esp, 32    

stdin

32 51 05
26 06 38
43 84 69
07 42 11

stdout

4

stderr

/usr/bin/ld: warning: cannot find entry symbol _start; defaulting to 00000000080480a0
Segmentation fault (core dumped)

strace