#include <stdio.h>

unsigned int ggT_C(unsigned int a, unsigned int b) {
  unsigned int res = 0;
  unsigned int div = 0;
  while(b !=0) { // while b not zero
    res = (a % b); // res = (a mod b)
    a = b; 
    b = res;
  }
  return a;
}

unsigned int ggT_Asm(unsigned int a, unsigned int b) {
  __asm {     
               mov edx, 0    ;
               mov eax, a    ; // EDX:EAX = a
               mov ecx, b    ; // ECX = b
    WhileLoop: cmp ecx, 0    ;
               jz EndLoop    ; // jump to "done" if ECX == 0
               div ecx       ; 
               mov eax, ecx  ; // EAX = ECX
               mov ecx, edx  ; // ECX = (a mod b)
               mov edx, 0    ; // EDX = 0 for next "div" command
               jmp WhileLoop ; 
    EndLoop:
  }
}


int main() {
  unsigned int a = 525;
  unsigned int b = 399;
  unsigned int result = ggT_C(a, b); // call function "ggT_C"
  printf( "ggT_C result = %d\n", result); // output result to console
  result = ggT_Asm(a, b); // call function "ggT_Asm"
  printf( "ggT_Asm result = %d\n", result); // output result to console

  return 0;
}