C Programming Code Examples
C > Conversions Code Examples
Program to Convert Numbers to Roman Numerals
/* Program to Convert Numbers to Roman Numerals
This program takes a decimal number and converts it to roman number.
Take a decimal number as input.
Check if the number is greater than 1000 or 900 or 500 or 400 or 100 or 90 or 50 or 40 or 10 or 9 or 5 or 4 or 1.
If it is, then store its equivalent roman number in a array.
Repeat the step 2-3 with the left over number. */
#include <stdio.h>
void predigit(char number1, char number2);
void postdigit(char c, int n);
char romanval[1000];
int i = 0;
int main()
{
int j;
long number;
printf("Enter the number: ");
scanf("%d", &number);
if (number <= 0)
{
printf("Invalid number");
return 0;
}
while (number != 0)
{
if (number >= 1000)
{
postdigit('M', number / 1000);
number = number - (number / 1000) * 1000;
}
else if (number >= 500)
{
if (number < (500 + 4 * 100))
{
postdigit('D', number / 500);
number = number - (number / 500) * 500;
}
else
{
predigit('C','M');
number = number - (1000-100);
}
}
else if (number >= 100)
{
if (number < (100 + 3 * 100))
{
postdigit('C', number / 100);
number = number - (number / 100) * 100;
}
else
{
predigit('L', 'D');
number = number - (500 - 100);
}
}
else if (number >= 50 )
{
if (number < (50 + 4 * 10))
{
postdigit('L', number / 50);
number = number - (number / 50) * 50;
}
else
{
predigit('X','C');
number = number - (100-10);
}
}
else if (number >= 10)
{
if (number < (10 + 3 * 10))
{
postdigit('X', number / 10);
number = number - (number / 10) * 10;
}
else
{
predigit('X','L');
number = number - (50 - 10);
}
}
else if (number >= 5)
{
if (number < (5 + 4 * 1))
{
postdigit('V', number / 5);
number = number - (number / 5) * 5;
}
else
{
predigit('I', 'X');
number = number - (10 - 1);
}
}
else if (number >= 1)
{
if (number < 4)
{
postdigit('I', number / 1);
number = number - (number / 1) * 1;
}
else
{
predigit('I', 'V');
number = number - (5 - 1);
}
}
}
printf("Roman number is: ");
for(j = 0; j < i; j++)
printf("%c", romanval[j]);
return 0;
}
void predigit(char number1, char number2)
{
romanval[i++] = number1;
romanval[i++] = number2;
}
void postdigit(char c, int n)
{
int j;
for (j = 0; j < n; j++)
romanval[i++] = c;
}
/* Take a decimal number as input and store it in the variable number.
Check if the number is lesser than 0. If it is, then print the output as "Invalid number".
Check if the number is greater than 1000 or 500 or 100 or 50 or 10 or 5.
If it is, then also check if the number is greater than 900 or 400 or 90 or 40 or 9 or4. If it is, then call the function predigit() and subtract the variable number by its equivalent number and override the variable number with this value.
Otherwise call the function postdigit() and divide the variable number by its equivalent number and get the quotient. Multiply the quotient with its equivalent number and decrement the variable number with this value.
In the function postdigit(), assign the equivalent roman number to the array romanval[].
In the function predigit(), assign the array romanval[] with the parameters of function.
Repeat the steps 3-5 until the variable number becomes zero.
Print the array romanval[] as output. */
Writes the C string pointed by format to the standard output (stdout). If format includes format specifiers (subsequences beginning with %), the additional arguments following format are formatted and inserted in the resulting string replacing their respective specifiers. printf format string refers to a control parameter used by a class of functions in the input/output libraries of C programming language. The string is written in a simple template language: characters are usually copied literally into the function's output, but format specifiers, which start with a % character, indicate the location and method to translate a piece of data (such as a number) to characters. "printf" is the name of one of the main C output functions, and stands for "print formatted". printf format strings are complementary to scanf format strings, which provide formatted input (parsing). In both cases these provide simple functionality and fixed format compared to more sophisticated and flexible template engines or parsers,
The if...else statement executes two different codes depending upon whether the test expression is true or false. Sometimes, a choice has to be made from more than 2 possibilities. The if...else ladder allows you to check between multiple test expressions and execute different statements. In C/C++ if-else-if ladder helps user decide from among multiple options. The C/C++ if statements are executed from the top down. As soon as one of the conditions controlling the if is true, the statement associated with that if is executed, and the rest of the C else-if ladder is bypassed. If none of the conditions is true, then the final else statement will be executed.
The for loop is used in the case where we need to execute some part of the code until the given condition is satisfied. The for loop is also called as a per-tested loop. It is better to use for loop if the number of iteration is known in advance. The for-loop statement is a very specialized while loop, which increases the readability of a program. It is frequently used to traverse the data structures like the array and linked list.
An array is defined as the collection of similar type of data items stored at contiguous memory locations. Arrays are the derived data type in C programming language which can store the primitive type of data such as int, char, double, float, etc. It also has the capability to store the collection of derived data types, such as pointers, structure, etc. The array is the simplest data structure where each data element can be randomly accessed by using its index number.
#include is a way of including a standard or user-defined file in the program and is mostly written at the beginning of any C/C++ program. This directive is read by the preprocessor and orders it to insert the content of a user-defined or system header file into the following program. These files are mainly imported from an outside source into the current program. The process of importing such files that might be system-defined or user-defined is known as File Inclusion. This type of preprocessor directive tells the compiler to include a file in the source code program. Here are the two types of file that can be included using #include:
While loop is also known as a pre-tested loop. In general, a while loop allows a part of the code to be executed multiple times depending upon a given boolean condition. It can be viewed as a repeating if statement. The while loop is mostly used in the case where the number of iterations is not known in advance. The while loop evaluates the test expression inside the parentheses (). If test expression is true, statements inside the body of while loop are executed. Then, test expression is evaluated again. The process goes on until test expression is evaluated to false. If test expression is false, the loop terminates.
Read formatted data from stdin. Reads data from stdin and stores them according to the parameter format into the locations pointed by the additional arguments. The additional arguments should point to already allocated objects of the type specified by their corresponding format specifier within the format string. In C programming, scanf() is one of the commonly used function to take input from the user. The scanf() function reads formatted input from the standard input such as keyboards. The scanf() function enables the programmer to accept formatted inputs to the application or production code. Moreover, by using this function, the users can provide dynamic input values to the application.
In C, the "main" function is treated the same as every function, it has a return type (and in some cases accepts inputs via parameters). The only difference is that the main function is "called" by the operating system when the user runs the program. Thus the main function is always the first code executed when a program starts. main() function is a user defined, body of the function is defined by the programmer or we can say main() is programmer/user implemented function, whose prototype is predefined in the compiler. Hence we can say that main() in c programming is user defined as well as predefined because it's prototype is predefined. main() is a system (compiler) declared function whose defined by the user, which is invoked automatically by the operating system when program is being executed.
C Program to Find the length of the linked list using Recursion. This program uses Recursive Function and calculates the length of a string. The user enters a string to find it's length. List
Finding the first digit of any number is little expensive than last digit. To find first digit of a number we divide the given number by 10 until number is greater than 10. At the end...
Status epilepticus, print help. Extract UTC time from string. Convert UTC to time string. Print help and exit. Convert INT utc value to timestring. Convert STR to INT utc time...
C program code input a character and check whether the character is alphabet or not using Conditional/Ternary operator ?:. How to check alphabets by conditional operator...
Declare recursive function to find factorial of a number. First let us give a meaningful name to our function, say fact(). Factorial Function accepts an integer input whose factorial is to
You can 'concatenate two strings' easily using standard library function strcat() but, in this C program 'concatenates two strings' manually without using 'strcat()' function. Calculate the
