TROUVER L'INVERSE D'UN NOMBRE DANS Z/PZ

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

long int minimum(long int  a0,long int  b0)
{
  if (a0<b0) 
	{return a0;}
  else 
	return b0;
}

long int maximum(long int  a1,long int  b1)
{
  if (a1>b1)
	{return a1;}
  else
	return b1;
}

long int premier_entre_eux(long int  a2,long int  b2)
{
  long int r1, r2,rt;
  r1=minimum(a2,b2);
  r2=maximum(a2,b2);
  while(rt>1)
  {
	rt=r1 % r2;
	if (rt<0) 
	rt+=r2;
	r1=r2;
	r2=rt;
  }
  if (rt==1) 
	{return 1;}
  else
  	return 0;
}

long int bezout(long int  a3, long int  b3)
{
  long int coeffs1, coeffs2, coeffst,  r1, r2, rt;
  if (premier_entre_eux(a3,b3)==0) 
	{return 0;}
  else
  {
  coeffs1=1; coeffs2=0;
  r1=minimum(a3,b3);
  r2=maximum(a3,b3);
  rt=r1 % r2;
  while (rt>1)
      {
	rt=r1 % r2;
	if (rt<0) 
	rt+=r2;
	coeffst=coeffs1-(r1/r2)*coeffs2;
	coeffs1=coeffs2;
	coeffs2=coeffst;
	r1=r2;
	r2=rt;
      }
  }
  return(coeffs2);
}

long int inverse(long int  a4,long int  m)
{
  long int  result, a5;
  a5= a4 % m;
  result=bezout(a5,m);
  result=result % m;
  if (result<0) 
	result+=m;
  return result;
}

void main()
{
  long int  nb, p;
  printf("\nNombre a inverser : ");
  scanf("%d",&nb);
  printf("Le modulo: ");
  scanf("%d",&p);
  if (inverse(nb,p)==0) 
	{printf("Probléme : %d et %d ne sont pas premiers entre eux.\n", nb,p);}
  else 
	printf("\n\nL'inverse de %d modulo %d est %d.\n", nb,p,inverse(nb,p));
  system("pause");
}