Long how many digits

Count the number of digits in a long integer entered by a user. Attention reader! Get hold of all the important mathematical concepts for competitive programming with the Essential Maths for CP Course at a student-friendly price. Simple Iterative Solution The integer entered by the user is stored in the variable n. Then the while loop is iterated until the test expression n! After the first iteration, the value of n will be and the count is incremented to 1. After the second iteration, the value of n will be 34 and the count is incremented to 2.

After the third iteration, the value of n will be 3 and the count is incremented to 3. At the start of the fourth iteration, the value of n will be 0 and the loop is terminated.

Then the test expression is evaluated for false and the loop terminates. Python3 Log based Python program to count number of digits in a number function to import ceil and log import math def countDigit n : return math. Floor Math. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.

See your article appearing on the GeeksforGeeks main page and help other Geeks. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above. Skip to content. Change Language. Related Articles. The byte data type can store whole numbers from to This can be used instead of int or other integer types to save memory when you are certain that the value will be within and The short data type can store whole numbers from to Try it Yourself » Int The int data type can store whole numbers from to In general, and in our tutorial, the int data type is the preferred data type when we create variables with a numeric value.

The long data type can store whole numbers from to This is used when int is not large enough to store the value. Note that you should end the value with an "L":. You should use a floating point type whenever you need a number with a decimal, such as 9. The float data type can store fractional numbers from 3. Note that you should end the value with an "f":. The double data type can store fractional numbers from 1. Note that you should end the value with a "d":. The precision of a floating point value indicates how many digits the value can have after the decimal point.

The precision of float is only six or seven decimal digits, while double variables have a precision of about 15 digits. Therefore it is safer to use double for most calculations. A boolean data type is declared with the boolean keyword and can only take the values true or false :.

Boolean values are mostly used for conditional testing, which you will learn more about in a later chapter. Two bytes is usually called a word, or short word though word-length depends on the application. A two-byte word is also the size that is usually used to represent integers in programming languages. A long word is usually twice as long as a word. A less common unit is the nibble which is 4 bits, or half of a byte. It is cumbersome for humans to deal with writing, reading and remembering individual bits, because it takes many of them to represent even fairly small numbers.

A number of different ways have been developed to make the handling of binary data easier for us. The most common is hexadecimal. In hexadecimal notation, 4 bits a nibble are represented by a single digit.

There is obviously a problem with this since 4 bits gives 16 possible combinations, and there are only 10 unique decimal digits, 0 to 9. This is solved by using the first 6 letters A.. F of the alphabet as numbers. The table shows the relationship between decimal, hexadecimal and binary. There are some significant advantages to using hexadecimal when dealing with electronic representations of numbers if people had 16 fingers, we wouldn't be saddled with the awkward decimal system.

Clearly hexadecimal is better suited to the task of representing binary numbers than is decimal. It is convenient to write the binary number with spaces after every fourth bit to make it easier to read. Converting back and forth to decimal is more difficult, but can be done in the same way as before. Octal notation is yet another compact method for writing binary numbers. There are 8 octal characters, Obviously this can be represented by exactly 3 bits.

Two octal digits can represent numbers up to 64, and three octal digits up to A byte requires 2. It is much less common today but is still used occasionally e. Exercises: Convert from decimal to hexadecimal Answer 7D0 Convert 3C from hexadecimal to decimal Answer 60 Convert from binary to hexadecimal Answer A7B Convert 7D0 from hexadecimal to binary Answer If you shift a hexadecimal number to the left by one digit, how many times larger is the resulting number?

Answer It was noted previously that we will not be using a minus sign - to represent negative numbers. We would like to represent our binary numbers with only two symbols, 0 and 1. There are a few ways to represent negative binary numbers. The simplest of these methods is called ones complement, where the sign of a binary number is changed by simply toggling each bit 0's become 1's and vice-versa.

This has some difficulties, among them the fact that zero can be represented in two different ways for an eight bit number these would be and To represent an n bit signed binary number the leftmost bit, has a special significance. The difference between a signed and an unsigned number is given in the table below for an 8 bit number.

If Bit 7 is not set as in the first example the representation of signed and unsigned numbers is the same. However, when Bit 7 is set, the number is always negative. For this reason Bit 7 is sometimes called the sign bit. Signed numbers are added in the same way as unsigned numbers, the only difference is in the way they are interpreted.

This is important for designers of arithmetic circuitry because it means that numbers can be added by the same circuitry regardless of whether or not they are signed.

To form a two's complement number that is negative you simply take the corresponding positive number, invert all the bits, and add 1. The example below illustrated this by forming the number negative 35 as a two's complement integer:.

So is our two's complement representation of We can check this by adding up the contributions from the individual bits. The same procedure invert and add 1 is used to convert the negative number to its positive equivalent. If we want to know what what number is represented by , we apply the procedure again. Since represents the number 3, we know that represents the number Exercises: Convert from binary to decimal Answer Convert from binary to decimal Answer 34 Convert from decimal to binary Answer In 'C', a signed integer is usually 16 bits.

What is the largest positive number that can be represented? Consider the following examples. Let's carefully consider the last case which uses the number As a 4 bit number this is represented as.