<> Offensive and defensive world REVERSE Newbies /game
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Look at the title and say there are 8 A circle of lights , Input required 1-8 number , The input number will change the state of the corresponding digital light （ On or off ）, And the front lamp and the rear lamp of the lamp will also change the state . input 0 Will turn off all the lights , When 8 When both lights are on flag Will appear .
Here, you can enter directly in order 1-8 The number is obtained directly flag
The other method is more troublesome , use IDA32 Bit open program
Find it first main function
Press when found f5 Disassemble
follow-up main0 Continue to jump
See one if sentence , And the condition of judgment, which is to get flag Conditions （ use 1 and 0 To judge 8 Lights on and off ）
When 8 Output when all lights are on flag, Follow up here sub_457AB4（）
Continue to jump , See Tips ,flag Right here
Write the script according to the algorithm
#include <stdio.h> #include <stdlib.h> int main(void) { int a[] = {18,64,98,5,2
,4,6,3,6,48,49,65,32,12,48,65,31,78,62,32,49,32, 1,57,96,3,21,9,4,62,3,5,4,1,2,3
,44,65,78,32,16,97,54,16,44, 52,32,64,89,45,32,65,15,34,18,16,0}; int b[] = {123
,32,18,98,119,108,65,41,124,80,125,38,124,111,74,49, 83,108,94,108,84,6,96,83,44
,121,104,110,32,95,117,101,99, 123,127,119,96,48,107,71,92,29,81,107,90,85,64,12
,43,76,86, 13,114,1,117,126,0}; for (int i = 0; i < 56; ++i) { b[i] ^= a[i]; b[i
] ^= 0x13; printf("%c",b[i]); } return 0; }
function , obtain flag
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