C++ Programming Code Examples
C++ > Conversions Code Examples
Convert Decimal to Octal
/* Convert Decimal to Octal
To convert decimal number to octal number in C++ programming, you have to ask to the user to enter the decimal number to convert it into octal number to display the equivalent value in octal format as shown here in the following program.
Following C++ program ask to the user to enter any number in decimal to convert it into octal, then display the result on the screen : */
#include<iostream.h>
#include<conio.h>
void main()
{
clrscr();
long int decnum, rem, quot;
int i=1, j, octnum[100];
cout<<"Enter any decimal number : ";
cin>>decnum;
quot=decnum;
while(quot!=0)
{
octnum[i++]=quot%8;
quot=quot/8;
}
cout<<"Equivalent octal value of "<<decnum<<" is : \n";
for(j=i-1; j>0; j--)
{
cout<<octnum[j];
}
getch();
}
The cin object is used to accept input from the standard input device i.e. keyboard. It is defined in the iostream header file. C++ cin statement is the instance of the class istream and is used to read input from the standard input device which is usually a keyboard. The extraction operator(>>) is used along with the object cin for reading inputs. The extraction operator extracts the data from the object cin which is entered using the keyboard. The "c" in cin refers to "character" and "in" means "input". Hence cin means "character input". The cin object is used along with the extraction operator >> in order to receive a stream of characters.
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Program which detects a key pressed and its 'ASCII' value with out pressing enter key and using cin>> on press Esc key program should exit. When press a key its ASCII value should
