Making numbers with pow()

[mrchaos]

I have a 4 positon array with characters (numbers) stored in it. For example 49, 50, 51, 52...which would be 1,2,3,4 respectively. What I want to do is build the number 1234 out of the array. This is the code I have so far and it doesn't seem to wanna work.

j=iFieldSz;
     for(i=0;i<iFieldSz;i++) {
          itemp = (int)(number[i] - 48);
          inumber += itemp * pow(10.0,(double)j);
          j--;
     }
     printf("%d",inumber); 

any help would be great

[Technocrat]

Your code worked for me once I set inumber to 0 to start and took the loop down one cycle. What problem are you having? What's the output?

[mrchaos]

I end up an inumber of -209399982

here is the entire function, maybe it will help clear things up a bit more

int getint(int iFieldSz) {

     char number[4];
     int inumber=0,bvalid=0,ipos=0,i,itemp,j;
     char c;

     for(i=0;i<4;i++)
          number[i] = 0;
     fflush(stdin);
     do {
          c = getch();
          if (strlen(number) < iFieldSz && isdigit(c)) {
               printf("%c", c);
               number[ipos++] = c;
          }
          if (c == '\\b' && ipos > 0) {
               printf ("\\b \\b");
               number[--ipos] = '\0';
          }
          if (c == '\r' && strlen(number) > 0)
               bvalid = 1;
     } while (! bvalid);
     j=iFieldSz;
     for(i=0;i<iFieldSz;i++) {
          itemp = (int)(number[i] - 48);
          inumber += itemp * pow(10.0,(double)j);
          j--;
     }
     printf("%d",inumber);
     return inumber;

} 

thanks a lot,
Steve

[Technocrat]

hmm well it works fine for me again. There are two problems I see, the first one might be your problem.

#1 - You are hard coding iFieldSz & number[] which is fine but you are not stoping your loop if 4 is being reached. Also what is the point of iFieldSz?
#2 - You are getting an extra 0 on your number at the end because you have j set to 4 but i starts at 0 so you need to take one away from j.

Here is the code I used:

#include <iostream>  //preprocessor statement
using namespace std;  //choosing the namespace that we are going to use
#include <conio.h> 
#include <math.h>
#include <stdio.h>

/*
    This is our main function, everything
    starts running here.
*/
int getint(int iFieldSz) {

     char number[4];
     int inumber=0,bvalid=0,ipos=0,i,itemp,j;
     char c;

     for(i=0;i<4;i++)
          number[i] = 0;
     fflush(stdin);
     do {
          c = getch();
          if (strlen(number) < iFieldSz && isdigit(c)) {
               printf("%c", c);
               number[ipos++] = c;
          }
          if (c == '\b' && ipos > 0) {
               printf ("\b \b");
               number[--ipos] = ' ';
          }
          if (c == '\r' && strlen(number) > 0)
               bvalid = 1;
     } while (! bvalid);
     j=iFieldSz-1;
     for(i=0;i<iFieldSz;i++) {
          itemp = (int)(number[i] - 48);
          inumber += itemp * pow(10.0,(double)j);
          j--;
     }
     printf("\r\n%d",inumber);
     return inumber;

}

int main()
{
    int q = getint(4);

    return 0; // quit back to the OS

} 

My input/output
3452
3452Press any key to continue
q = 3452

[mrchaos]

What complier are you using for that? I have Dev C++ 4...i'm starting to think that it maybe the problem

[Technocrat]

MSVC 7

[CornedBee]

Even DevC++4 should be able to compile this correctly.