///////    File NewEng.C    ///////
#include <math.h>
#include  "NewEng.h"

const char* NewEng::keys = "+-*/=^NnAaCcQqMmRrSsKk";

void NewEng::allclear()
{     cnst = m = 0.0; 
      CalcEng::allclear();
}

int NewEng::pre_oper(char c)
{    switch( c )
     {    case 'A': case 'a': // AC
                allclear(); 
                return 1;
          case 'R': case 'r': // MR
                operand(m);   // darg=argcnt-1;
                return 1;
          case 'K':           // constant recall
                operand(cnst);// darg=argcnt-1;
                return 1;
          case 'S': case 's': // sqrt
                op = '=';
                if (argcnt == 2) ans =  arg;
                if ( ans < 0.0 ) err_flag = 1;
                else ans = sqrt(ans);
                return 1;
     }
     return 0;
}

void NewEng::operate(char c)
{    if ( pre_oper(c) ) return;
     CalcEng::operate(c);
     post_oper(c);
}

void NewEng::post_oper(char c)
{    switch( c )
     {    case 'M': // M+
                m += ans;
                op = '=';  break;
          case 'm': // M-
                m -= ans;
                op = '=';  break;
          case 'k': // keep as constant
                cnst = ans;
                op = '=';  break;
     } 
}