define String to number

[ehsangha]

Hi

I want to Define when user enter a character. the character return a number . for example when user enter "A" this character define 1

[Bazzy]

what?

[ehsangha]

Hi
for example when user enter A . the Compiler return 1

[ehsangha]

hi
#define a 1;
int main()
{
char st;
cin >> st; // for example a
cout << st ; // the output is a

}
I want the output is 1

[Bazzy]

Like this?

int main()
{
    char st;
    cin >> st;
    if ( st == 'a' )
        cout << 1 ;
   return 0;
}

http://www.cplusplus.com/doc/tutorial/control/#if

[ehsangha]

No :(

[tummychow]

Well then what do you want? You can't output a character as a number with cout.

[choisum]

char input1 = 'A';
char input2 = 'b';
std::cout << input1 - 'A' + 1 << std::endl ;
std::cout << input2 - 'A' + 1 << std::endl ;

Here's one interpretation, which is warmer, though likely not quite what OP is looking for.

[iansutton]

For starters you can convert any character to an integer. Assuming you have an ANSI character you can use atoi. Personally I don't like this, it always seems a bit too C like to me, but it works (I'm sure theres an alternative, I know there is for c# etc.)

int char_ansi_id = atoi(entered_char);

Now, if it was upper case: A=65-Z=90. Lower case: a=97-z=122

Source: http://www.alanwood.net/demos/ansi.html

int input_val = 0;

if (char_ansi_id >= 65 && char_ansi_id <= 90)
input_val = char_ansi_id - 64
else
input_val = char_ansi_id - 97


Obviously there would need to be som error checking thrown in i.e. if the character entered isn't in those bounds. But I'm sure you can handle that.

[iansutton]

Don't expect that code to compile by the way, its was meant simply as a guider not a complete homework solution.

[magnificence7]

I think he means something like:

int main()
{
    char st;
    cin >> st;
    if ( st == 'a' )
        return 1;
   return 0;
}

But if you really mean that the compiler should return a code, idc...

[jwC5fSEw]

char a = 'a';
cout << a - '0';

This outputs 49. Doing the same with 'b' outputs 50, with 'c' outputs 51, and so on. If you want the lower-case alphabet to correspond with numbers starting from 1, you could just use (a - '0') - 48.

[ehsangha]

ok Thank you