Problem converting from char array to int array.

**TheUmer** · 03-26-2010

I'm using the following code to do so:

Code:

#include <stdio.h>

int main ()
{
int i;
char ch[20]="1 2 34 4 56672332432";
int ch1[20];
for (i=0; i<20; i++)
{
      ch1[i]=(int)ch[i]-'0';
}
for (i=0; i<20; i++)
{
      printf ("%d\n ", ch1[i]);
}
return 0;
}

The problem is I can't an integer more than 9 as it is. For example, the array is reading and converting each char separately, so for example if I want to get 34 form char array into an integer 34, it won't do so. It picks and gives 3 separately and 4 separately.

What should I do for this problem?

**tabstop** · 03-26-2010

Use sscanf instead.

**TheUmer** · 03-26-2010

Ok, instead of the following code:

Code:

for (i=0; i<20; i++)
{
      ch1[i]=(int)ch[i]-'0';
}

I tried the following:

Code:

for (i=0; i<20; i++)
{
sscanf("%s", ch1);
}

and also:

Code:

for (i=0; i<20; i++)
{
ch1[i] = sscanf("%s", ch);
}

But neither works. What would be the proper code?

**laserlight** · 03-26-2010

Let's clarify what you are trying to do. Are you trying to convert the string "1 2 34 4 56672332432" into a sequence of 5 integers, 1, 2, 34, 4 and 56672332432?

**TheUmer** · 03-26-2010

String would be: ""1 2 34 4 56"

I want to read this as an int array of size 5.

**laserlight** · 03-26-2010

Ah. Okay, one approach is to use a stringstream. The idea is to treat the string as if it were the contents of a file. For example:

Code:

#include <iostream>
#include <string>
#include <sstream>

int main()
{
    using namespace std;
    string str = "1 2 34 4 56";

    stringstream ss(str);
    int numbers[5];
    for (int i = 0; i < 5; ++i)
    {
        ss >> numbers[i];
    }

    for (int i = 0; i < 5; ++i)
    {
        cout << numbers[i] << '\n';
    }
}

**TheUmer** · 03-26-2010

This is C++. I'm doing in C.

**laserlight** · 03-26-2010

Right. This thread has been moved to the C programming forum.

**TheUmer** · 03-26-2010

oh sorry, I didn't know I was in C++ forum! :s

**tabstop** · 03-26-2010

Originally Posted by TheUmer

Ok, instead of the following code:

Code:

for (i=0; i<20; i++)
{
      ch1[i]=(int)ch[i]-'0';
}

I tried the following:

Code:

for (i=0; i<20; i++)
{
sscanf("%s", ch1);
}

and also:

Code:

for (i=0; i<20; i++)
{
ch1[i] = sscanf("%s", ch);
}

But neither works. What would be the proper code?

Have you used any scan functions before? Have you even bothered to look up sscanf anywhere at all?

**vart** · 03-26-2010

Code:

#include <stdio.h>

int main ()
{
    int count = 0;
    int i;
    char ch[20]="1 2 34 4 56";
    int num[20];
    int poz;
    const char* str = ch;
    while(sscanf(str,"%d%n",&num[count], &poz) == 1)
    {
        count++;
        str += poz;
        if(count == 20) break;
    }
    for (i=0; i<count; i++)
    {
        printf ("%d\n", num[i]);
    }
    return 0;
}

**TheUmer** · 03-26-2010

@vart:

Thanks a lot. That really worked. I'm highly obliged. Now I can carry on with my assignment.

Thread: Problem converting from char array to int array.

Thread Tools

Search Thread

Display

Problem converting from char array to int array.

Similar Threads

Function argument assignment between types "unsigned int" and "unsigned long"

Screwy Linker Error - VC2005

Converting a circulating mouse pointer to use a Potentionmeter

Half-life SDK, where are the constants?

My graphics library