how to find digit of a number in c

Divide the number by 10. reverse. You'd read it into a char* using the fread() function, and then store how many bytes were read in a separate variable. Count = log10(Number); FirstDigit = Number / pow(10, Count); printf(" \n The First Digit of a Given Number %d = %d", Number, FirstDigit); return 0; } The output of the above c program; as follows: Please Enter any Number that you wish : 123 The First Digit of a Given Number 123 = 1. The number of digits can Calculate floor(pow(2,n)/10) mod 10 - sum of digits of pow(2,n), C++ program in which, read a six digit integer as input from user and output each of its digit in words by for/ While loop, C++ unable to index an element of an array using a nested loop. Some of our partners may process your data as a part of their legitimate business interest without asking for consent. And then, it is going to find the Last Digit of the user-entered value. This way you can get all the digits. Declaring the number size in advance is both tedious and unnecessary. How do you understand the kWh that the power company charges you for? Even if it's not originally a string, it's more optimal to convert it to one and then count the characters (std::count is the way to go in C++). c++ how to check each digit in an integer and compare it to the base number. @BenKey - when I wrote this C++11 hadn't come into existence yet so, Note, however, that although your solution is indeed very 'simple', it also yields the number's component digits in. How and why does electrometer measures the potential differences? To deal with non-integer results you can use the floor()+1 trick. If N = 12345. len = (int)log 10 (12345) + 1 = 5. replacing tt italic with tt slanted at LaTeX level? We can also count the number of digits with the help of the logarithmic function. Here we will see how to check how many digits are there in an integer in C++. A simple solution would be to use the log 10 of a number. Enter the number and keep it as a string. How to separate digits from a number in C++? I want my program to identify the separate digits in a given number, like if I input 4692, it should identify the digits and print 4 6 9 2. This was masked by the printf("%1d", quot); since it would print a 2 digit number despite the %1d format string. Extracting digits of a number using C program without Method 1: Convert the number into a string array, which can be accomplished by sprintf. You can count the digits your number have then it's easy. We and our partners use data for Personalised ads and content, ad and content measurement, audience insights and product development. In func(), we declare a static variable, i.e., counter, which will be initialized only once. Before this fix, if the input was a power of 10, the first instance of quot would be 10, a 2 digit number, when the goal is a single digit number. Enhance the article with your expertise. How and why does electrometer measures the potential differences? What is the use of explicitly specifying if a function is recursive or not? Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, The future of collective knowledge sharing. C++ get each digit in int - Stack Overflow For example if the random numbers are 144566888, then the output would be. Extracting digits of a number using C program without using The header should look like: bool containsDigit (int number, int digit); If number contains digit, then the function should return true. How to find Note: If the position get increased then the number of zeros in modulo and in divide also increases: Need len to make sure we don't over-run the array. How to identify specific digits Don't be so harsh, @Benoit thanks for your comment. We use a Decimal / Base 10 number system. Get the length of the (remaining) number by calculating log10 (value). How does momentum thrust mechanically act on combustion chambers and nozzles in a jet propulsion? Basically I would like to make a small little program that when u enter a number (say 145) it read the 3 digits and prints the largest one. We will create a while loop that iterates until the value of 'n' is not equal to zero. How to count each digit in a range of integers? * If the number is arriving as text, do you even need to convert it to a proper numeric if they are hexadecimal then it is possible. Otherwise, print No. @BasileStarynkevitch: it would be trivial with array, but I dont want to use array, as I dont want to use logical operators. Web6 Answers Sorted by: 5 Change int on the first line to char. This article is being improved by another user right now. visibly in reverse order. How to extract digits from a number in C? Begining from Methods to Count Digits of a Number 1. Works for positive numbers only. In conclusion, the @hoyhoy answer is more optimized than yours, as you need to first convert the integer and then count characters, New! Find centralized, trusted content and collaborate around the technologies you use most. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. Why would a highly advanced society still engage in extensive agriculture? Before this fix, if the input was a power of 10, the first instance of quot would be 10, a 2 digit number, when the goal is a single digit number. C++ unable to index an element of an array using a nested loop. I'm pretty sure this can be done since I've once used a similar method to extract the red green and blue values from a hexadecimal colour value. replacing tt italic with tt slanted at LaTeX level? To view the purposes they believe they have legitimate interest for, or to object to this data processing use the vendor list link below. What is known about the homotopy type of the classifier of subobjects of simplicial sets? WebC++ Program to Find number of Digits from any number. The integer entered by the user is stored in variable n. Then the dowhile loop is iterated until the test expression n! "during cleaning the room" is grammatically wrong? C Program to Find Last Digit Of a Number - Tutorial Gateway find OverflowAI: Where Community & AI Come Together. replacing tt italic with tt slanted at LaTeX level? You need to tell us exactly how your numbers are being stored, as this will dictate the best approach. Not the answer you're looking for? I stumbled across this challenge when I needed to calculate a check number/digit from the individual digits of the number itself. Contribute to the GeeksforGeeks community and help create better learning resources for all. WebA simple way to find the length (i.e number of digits) of signed integer is this: while ( abs(n) > 9 ) { num /= 10; ++len; } Where n is the integer you want to find the length of and where len is equal to the number of digits in the integer. PS: This works for integers, not for numbers with decimals (in that case you should know what's the precision of the type you are using). Copyright Tuts Make . You can get a look at value just by blinking a single led :). What if you shift it (FO) right by 4 and do bitwise and again? from 547 to 47 to 7)? (The setting of number[digit] is already done.) WebNow, we will see how to count the number of digits without using a loop. Making statements based on opinion; back them up with references or personal experience. This integer is nothing but the number entered by the user. This was masked by the printf("%1d", quot); since it would print a 2 digit number despite the %1d format string. How can I use ExifTool to prepend text to image files' descriptions? :). lookup table indipendent; using namespace std; Not enough information in the question. We can also count the number of digits with the help of the logarithmic function. All 4 digit numbers must be greater than or equal to 1,000 and less than or equal to 9,999. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. I don't exactly understand how this works. WebA year ago, a new three-digit phone line launched nationwide, making it easier for people facing a mental health crisis and other issues to find resources and support. It would be trivial with arrays, but I don't want to use array, and I don't want to use logical operators. return 1; int count = 0; while (n != 0) { n = n / 10; ++count; } return count; } int main (void) { long long n = 345289467; cout << "Number of digits : " << countDigit (n); return 0; } After the first iteration, the value of n will be 345 and the count is incremented to 1. thanks! To subscribe to this RSS feed, copy and paste this URL into your RSS reader. When the first iteration executes, the value of 'n' will be 123, and the value of count will be incremented to 1. c++ I seek a SF short story where the husband created a time machine which could only go back to one place & time but the wife was delighted. Extracting individual digits from a Is the DC-6 Supercharged? Using unsigned long long would for both the vector and the data type of num would fix both of these issues. The corrected solution I've provided avoids this problem also. Count of subsequence of an Array having all unique digits. c base = 2 - specify our base is 2 (binary) solution = "" - create an empty string in which we will concatenate our solution. Since 10 is not a power of 2, you will not be able to use bitwise operators. Look at reverse_find, or find_reverse, or something like that. And yeah, without using arrays. C program to find first and last digit of any number - Codeforwin Are self-signed SSL certificates still allowed in 2023 for an intranet server running IIS? I don't test it just write what is in my head. Beginner c++ How to return the number of digits in a number? c++ We will create a C program to count the number of digits using functions. Execute the code block inside the statement till the condition passes. I know the question has been answered, but I shall post this answer in case anyone finds it useful. #include digits one at a time to other variables. Edit: int countDigits (int p_num) { int nbDigits = 0; if (p_num == 0) return 1; while (p_num != 0) { p_num /= 10; nbDigits++; } return nbDigits; } This solution also fails for any number with 0 digits in the least significant position or positions. Quickest not necessarily best. How can I use ExifTool to prepend text to image files' descriptions? In C The main character is a girl. So, knowing that, you can simply loop over the number, adding those values and dividing by a please specify. How to grab first digit of an int in an int array? After the completion of the third iteration, the value of 'n' becomes 0, and loop is terminated as it does not satisfy the condition (n!=0). PS: This works for integers, not for numbers with decimals (in that case you should know what's the precision of the type you are using). C This, of course, would give me 8. Is any other mention about Chandikeshwara in scriptures? Web6 Answers Sorted by: 5 Change int on the first line to char. of digits. So to get the number of digits of a number x in base b you can use the inverse function of exponentiation: base-b logarithm. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Here is my attempt at futility: I have seen many answers, but they all forgot to use do {} while() loop, which is actually the canonical way to solve this problem and handle 0 properly. Next time, do your own homework. Developed by JavaTpoint. C program to find and print first and last digit of a number; Through this tutorial, we will learn how to find and print first and last digit of a number in c program using log() & pow() , while loop. Modulo in order to get single int from long, C Language - add products digits (i.e., not the products themselves). C Here is my try. Works for positive numbers only. Max range 2^64 (unsigned long long) #include A little correction: There's a better way to print the decimal digits from left to right, without allocating extra buffer. Your code is broken. C Program to Find First Digit Of a Number - Tutorial Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, The future of collective knowledge sharing, The only way to convert an integer to string, is using division/modulus. The first problem arises because you're trying to find the first power of ten above the number but, at some point, multiplication will wrap around. Get all the individual digits into something like an array - two variants: Thanks for contributing an answer to Stack Overflow! The number of digits can be calculated by using log10(num)+1, where log10() is the predefined function in math.h header file. By clicking Post Your Answer, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct. C Program to Count Number of Digits in an Integer The program will crash if you go over the end of a string, or worse it may continue running, but have a messed up internal state. Making statements based on opinion; back them up with references or personal experience. Did active frontiersmen really eat 20,000 calories a day? And yeah, without using arrays. Sci fi story where a woman demonstrating a knife with a safety feature cuts herself when the safety is turned off. How to get the digits of a number without converting it to a string/ char array? Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, The future of collective knowledge sharing, Since I did not find it in my personal bit operator compendium (. @Nippey: what's the differente between "number of digits" and "digits of a number"? Input: 147 9 Output: false. The very first invocation of getGreatestDigit(num) can compare the number it took with the greatest number returned from all recursive calls. How do I extract the digits of a number in C++? The func(n/10) will be called recursive1y until the condition (n>0) is true. Therefore middle digit of N = last digit of First half of N = (First half of N) % 10 = 123 % 10 = 3. This solution also fails due to overflow when score >= ceil (INT_MAX / 10.0). Write C++ program to find first and last digit This allows snprintf () to be called with the str parameter NULL and the size parameter 0, e.g. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. For convert a number to a string, you may can use the function itoa, so considering the variant with the modulo of a number in a loop. How and why does electrometer measures the potential differences? And get off of my lawn! @tunnuz: This was no good answer as this gave the number of digits and not the digits of a number as requested. Required fields are marked *. Not the answer you're looking for? Webnum = num / 10; } We have used for loop to count the total no. If you want the most significant digit first, you'll have to store the digits in an array, then read them out in reverse order.