A simple question about input a constant in C

[runsun]

I want to input (scanf) an integer, then treat (or define) it as a constant. How do I do?

[weaknessforcats]

You typecast the variable to a const:

int x;
scanf("%d", &x);
const int y = (const int)x;
y = 10; /* error! */
 

Then use the typecast variable in your code instread of the original.

[runsun]

You typecast the variable to a const:

int x;
scanf("%d", &x);
const int y = (const int)x;
y = 10; /* error! */
 

Then use the typecast variable in your code instread of the original.

I tried. It does not work...

[Silent1Mezzo]

I tried. It does not work...

Which part doesn't work....where are you getting errors. The code above should work perfectly.

[runsun]

Which part doesn't work....where are you getting errors. The code above should work perfectly.

I think this may be the problem:
I define all the functions; then a number is inputted and it is defined as a constant (say, y, using the code that weaknessforcats posted); after that, the functions are called.
I guess the functions should be defined after the constant is defined, because come of them use the constant (y).
I'll try this soon...

[Silent1Mezzo]

I think this may be the problem:
I define all the functions; then a number is inputted and it is defined as a constant (say, y, using the code that weaknessforcats posted); after that, the functions are called.
I guess the functions should be defined after the constant is defined, because come of them use the constant (y).
I'll try this soon...

When you declare the functions are you declaring the const variable constant?

e.g
function prototype

void functionOne(const int y);

call

functionOne(y);

I sometimes forget to put it as a constant in the function.

[runsun]

Which part doesn't work....where are you getting errors. The code above should work perfectly.

I tested. It is nothing to do with where functions declared. I think I did exactly as
the code provided. Here are first part of my code and the error message:

Code: ( c )
#include <stdio.h>
void main ()
{
int max;
int a[10], i;
printf ("enter total number: ");
scanf ("%d", &max);
const int maxmium = (const int) max;
printf ("enter some integers: ");
for (i=0; i<maximum; i++)
scanf ("%d", &a[i]);
...
errors:
line 8: parse error before `const'
line 10: `maximum' undeclared (first use in this function)

[ilikepython]

I tested. It is nothing to do with where functions declared. I think I did exactly as
the code provided. Here are first part of my code and the error message:

Code: ( c )
#include <stdio.h>
void main ()
{
int max;
int a[10], i;
printf ("enter total number: ");
scanf ("%d", &max);
const int maxmium = (const int) max;
printf ("enter some integers: ");
for (i=0; i<maximum; i++)
scanf ("%d", &a[i]);
...
errors:
line 8: parse error before `const'
line 10: `maximum' undeclared (first use in this function)

You misspelt maximum("maxmium") and when I fixed that it works fine.