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Code: Select all

# include <stdio.h>
# include <values.h>

int main (int argc, char** argv)
{
        signed int i;
        for (i=MININT; i<MAXINT; i++)
        {
        register arg=i;
        register arg1=arg;
        arg=arg>>0x1f;
        arg=~arg;
        arg=arg&arg1;
        arg-=0x6fe5d5;
        arg=arg^0x2eb22189;
        arg=arg*0x1534162;
        arg=arg^0x69f6bc7;
        if (arg==230392619) {printf("%i\n",i);}
        }
}

Code: Select all

#include <iostream>
int main()
{
	int out = 230392619;
	
	// 1. bruteforce
	/*for( int i = 0; ; ++i )
	{
		int edx = i;
		edx -=	0x6FE5D5;
		edx ^=	0x2EB22189;
		edx *=	0x1534162;
		edx ^=	0x69F6BC7;
		
		if( edx == out )
		{
			std::cout << i << std::endl;
			break;
		}
	}*/

	// 2. inversion
	int x, edx = out;
	edx ^=	0x69F6BC7;
	
	// inversion of the multiplication: can this be done more efficiently?
	for( x = 0 ; x * 0x1534162 != edx ; ++x ); edx = x; 
	
	edx ^=	0x2EB22189;
	edx +=	0x6FE5D5;
	std::cout <<  edx << std::endl;
	

	return 0;
}

Code: Select all

#include "stdafx.h"
#include "stdio.h"

int main(int argc, char* argv[])
{
	unsigned int j;
	for(unsigned int i=0; i<0xFFFFFFFF; i++) {
	_asm {
		push    eax
		push    edx
		mov     eax, i
		mov     edx, eax
		sar     edx, 1Fh
		not     edx
		and     edx, eax
		sub     edx, 0x6FE5D5
		xor     edx, 0x2EB22189
		imul    edx, 0x1534162
		xor     edx, 0x69F6BC7
		mov     j, edx
		pop     edx
		pop     eax
	}
		if(j == 230392619)
			break;
	}
	printf("%d\n", i);
	return 0;
}

Code: Select all

public class Blackbox {
	public static void main(String[] args) {	
		int x = 0;
		int s = 230392619;
		int i = 0;
		int ul = Integer.MAX_VALUE;		
		while (x!=s) {
			x = ((( ul & i - 7333333 ) ^ 783425929 ) * 22233442 ) ^ 111111111;
			i++;
		}
		System.out.println("Solution:"+(i-1));
	}
}

Code: Select all

		int i, d = 0;
 
		i = 230392619;
		i ^= 0x69f6bc7;
		d = i / 0x1534162;
		while (d++ * 0x1534162 != i);
		i = d ^ 0x2eb22189;
		i += 0x6fe5d5;

Code: Select all

#!/usr/bin/env bash
max=2147483647
threads=100
steps=$((max / threads + 1))

function test {
        local s=$1
        local e=$2
        local t=$3

        while [[ $s -lt $e ]]; do
                v=`./onetest $s`
                echo "$s = $v" | tee status.$t.log | grep 230392619
                s=$((s + 1))
        done
}

for (( i=0; i<$threads; i++ )); do
        s=$((i * steps))
        e=$(((i + 1) * steps))
        ((test $s $e $i &) &)
done

Code: Select all

#include <stdio.h>
#include <stdlib.h>

#define SAR_CONSTANT    0x1F
#define SUB_CONSTANT    0x6FE5D5
#define XOR_CONSTANT_1  0x2EB22189
#define MUL_CONSTANT    0x1534162
#define XOR_CONSTANT_2  0x69F6BC7

inline int onetest(int input)
{
	int temp;
	temp = input;
	
	input = (input >> SAR_CONSTANT);   // SAR
	input = (~input);                  // NOT
	input = (input & temp);			   // AND
	input = (input - SUB_CONSTANT);    // SUB
	input = (input ^ XOR_CONSTANT_1);  // 1st XOR
	input = (input * MUL_CONSTANT);    // IMUL
	input = (input ^ XOR_CONSTANT_2);  // 2nd XOR
	
	return input;
}

int main(int argc, char** argv)
{
	unsigned int i;
	
	for (i=0; i<0xFFFFFFFF; i++)
	{
		if ( onetest(i) == 230392619 )
			printf("Solution: %d\n", i);
	}
	
	return 0;
}

Code: Select all

#include <stdio.h>

int main(int argc, char **argv, char **envp) {
	for (int i = 0; i <= 2147483647; i++) {
		if ((22233442 * (((i & ~(i >> 31)) - 7333333) ^ 0x2EB22189) ^ 0x69F6BC7) == 230392619) {
			printf("%d\n", i);
			break;
		}
	}
}