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C program to convert Decimal to Octal number system



C program to convert Decimal to Octal number system

Write a C program to input decimal number from user and convert to octal number system. How to convert from decimal number system to octal number system in C programming.

Decimal number system
Decimal number system is a base 10 number system. Decimal number system uses 10 symbols to represent all numbers i.e. 0123456789.

Octal number system
Octal number system is a base 8 number system. Octal number system uses 8 symbols to represent all numbers i.e. 01234567

Algorithm to convert decimal to octal

Algorithm Decimal to Octal conversion
    begin:
        read(decimal);
        octal = 0; place = 1; rem = 0;
        While (decimal > 0) do
            begin:
                rem = decimal % 8;
                octal = (rem * place) + octal;
                place = place * 10;
                decimal = decimal / 8;
            end;
        print('Octal number' octal);
    end;

#include <stdio.h>

int main()
{
    long long decimal, tempDecimal, octal;
    int i, rem, place = 1;

    octal = 0;

    /* Input decimal number from user */
    printf("Enter any decimal number: ");
    scanf("%lld", &decimal);

    tempDecimal = decimal;

    /* Decimal to octal conversion */
    while(tempDecimal > 0)
    {
        rem = tempDecimal % 8;

        octal = (rem * place) + octal;

        tempDecimal /= 8;

        place *= 10;
    }

    printf("\nDecimal number = %lld\n", decimal);
    printf("Octal number = %lld", octal);

    return 0;
}