#include "stdio.h"
#include "malloc.h"
int main (int argc, char **argv)
{
FILE *f_in = fopen("PP.zip","rb");
FILE *f_out = fopen("pp.pdf","wb");
unsigned int dlzka;
if (!f_in || !f_out)
return -1;
fseek(f_in, 0, SEEK_END);
dlzka=ftell(f_in);
fseek(f_in, 0, SEEK_SET);
unsigned char *buffer = (unsigned char *) malloc(dlzka);
if(!buffer)
return -1;
fread( buffer, dlzka, 1, f_in);
printf("Dlzka %u", dlzka);
for(int n = 0 ; n < dlzka ; n++)
buffer[n] =(unsigned char) (((unsigned int)buffer[n] + 251) % 256);
fwrite (buffer, dlzka, 1, f_out);
free(buffer);
fclose(f_in);fclose(f_out);
return 0;
}