Someone

int     my_putstr(char *str);
#include <stdlib.h>
#include <unistd.h>
void    my_putchar(char c);

int     str_is_op(char *str, int i)
{
  if (str[i] == '+' || str[i] == '-' || str[i] == '/' || str[i] == '*' || str[i] == '%' ||
      str[i] == '(' || str[i] == ')')
    {
      return (1);
    }
  else
    {
      return (0);
    }
  return (2);
}

char    *parser(char *str, int taille)
{
  int   var1;
  int   var2;
  char  *dest;
  char  *stack;

  stack = malloc(sizeof(*stack)*taille + 1);
  dest = malloc(sizeof(*dest)*taille + 1);
  var1 = 0;
  var2 = 0;
  while (str[var1 + var2])
    {
      if (str_is_op(str, var1 + var2))
        {
        stack[var1] = str[var1 + var2];
        var1++;
        }
      if (!str_is_op(str, var1 + var2))
        {
          dest[var2] = str[var1 + var2];
          var2++;
        }
    }
  stack[var1] = '\0';
  dest[var2] = '\0';
  return (dest);
}

int     main()
{
  my_putchar(parser("-49+1984", 9)[0]);
  return (0);
}