- C Programming Examples
- C Programming Examples
- C Print Hello World
- C Get Input from User
- C Print Integer
- C Add Two Numbers
- C Add Subtract Multiply Divide
- C Add n Numbers
- C Area Perimeter of Square
- C Area Perimeter of Rectangle
- C Area Circum of Circle
- C Fahrenheit to Celsius
- C Celsius to Fahrenheit
- C Inches to Centimeters
- C Kilogram to Gram
- C Reverse a Number
- C Swap Two Numbers
- C Interchange Numbers
- C Print ASCII Value
- C Print Fibonacci Series
- C Check Palindrome or Not
- C Check Armstrong or Not
- C Find Armstrong Numbers
- C Find nCr and nPr
- C Find Profit Loss
- C Sum of their Square
- C First & Last Digit Sum
- C Sum of All Digit
- C Product of All Digit
- C Print Total Digit in Number
- C Check Perfect Number
- C Find Basic Gross Salary
- C Round Number to Integer
- C Print Series upto n Term
- C Find Factors of Number
- C if-else & Loop Programs
- C Check Even or Odd
- C Check Prime or Not
- C Check Alphabet or Not
- C Check Vowel or Not
- C Check Leap Year or Not
- C Is Reverse Equal Original
- C Make Calculator
- C Add Digits of Number
- Count Positive Negative Zero
- C Largest of Two Numbers
- C Largest of Three Numbers
- C Smallest of Two Numbers
- C Smallest of Three Numbers
- C Find Factorial of Number
- C Find LCM & HCF
- C Find LCM of n Numbers
- C Find HCF of n Numbers
- C Find Arithmetic Mean
- C Find Average, Percentage
- C Find Student Grade
- C Print Table of Number
- C Print Prime Numbers
- C Find Discount Purchase
- C Calculate Parcel Charge
- C Calculate Wage of Labor
- C Print Phone Bill
- C Conversion programs
- C Decimal to Binary
- C Decimal to Octal
- C Decimal to Hexadecimal
- C Binary to Decimal
- C Binary to Octal
- C Binary to Hexadecimal
- C Octal to Decimal
- C Octal to Binary
- C Octal to Hexadecimal
- C Hexadecimal to Decimal
- C Hexadecimal to Binary
- C Hexadecimal to Octal
- C Pattern Programs
- C Pattern Printing Programs
- C Print Diamond Pattern
- C Print Floyd's Triangle
- C Print Pascal's Triangle
- C Array Programs
- C 1D Array Programs
- C Linear Search
- C Binary Search
- C Largest Element in Array
- C Smallest Element in Array
- C Second Largest/Smallest
- C Count Even Odd
- C Array Element at Even
- C Array Element at Odd
- C Print Even Array Elements
- C Print Odd Array Elements
- C Sum/Product of Even/Odd
- C Reverse an Array
- C Insert Element in Array
- C Delete Element from Array
- C Merge Two Arrays
- C Bubble Sort
- C Selection Sort
- C Insertion Sort
- C Print Common Elements
- C 2D Array Programs
- C Add Two Matrices
- C Subtract Two Matrices
- C Transpose a Matrix
- C Multiply Two Matrices
- C Sum All Matrix Elements
- C Largest Element in Matrix
- C Print Row Column Total
- C 3D Array Programs
- C String Programs
- C Print String
- C Find Length of String
- C Compare Two String
- C Copy a String
- C Concatenate String
- C Reverse a String
- C Count Vowels Consonants
- C Replace Vowel in String
- C Delete Vowels from String
- C Delete Word from String
- C Frequency of Character
- C Count Word in String
- C Remove Spaces from String
- C Sort a String
- C Sort String in Alphabetical
- C Sort Words in Ascending
- C Sort Words in Descending
- C Uppercase to Lowercase
- C Lowercase to Uppercase
- C Swap Two Strings
- C Check Anagram or Not
- C Check Palindrome String
- C Print Number in Words
- C Print Successive Character
- C Character without Space
- C Remove Extra Spaces
- C File Programs
- C Read a File
- C Write Content to File
- C Read & Display File
- C Copy a File
- C Merge Two Files
- C Reverse File
- C Count All Character in File
- C List Files in Directory
- C Encrypt & Decrypt a File
- C Delete a File
- C Misc Programs
- Generate Random Numbers
- C Print Date Time
- C Print Message with Time
- C Get IP Address
- C Print Smiling face
- C Pass Array to Function
- Add Two Numbers using Pointer
- C Address of Variable
- C Shutdown Computer
- C Programming Tutorial
- C Tutorial
- C Programming Library
- C Standard Library
- C Programming Test
- C Programming Test
- Give Online Test
- All Test List
C Program to Find Length of String
In this tutorial, you will learn and get code about how to find and print the length of any given string by user (at run-time) using following approaches:
- using strlen() Function
- without using strlen() Function
- using user-defined Function
Print length of String using strlen() Function
To find the length of any given string in C programming, you have to ask from the user to enter the string and then find its length using strlen() function of string.h library as shown in the program given below:
#include<stdio.h> #include<conio.h> #include<string.h> int main() { char str[20]; int len; printf("Enter the string: "); gets(str); len = strlen(str); printf("\nLength of the string = %d", len); getch(); return 0; }
As the above program was written under Code::Blocks IDE, therefore after successful build and run, here is the first snapshot of sample run:
Now supply any string say codescracker and press ENTER
key to see the length of given string as shown here in the second snapshot:
The function named strlen() takes one argument as string and will return the length. Therefore, here the length of the string say str gets returned by the function strlen() and initialized to the variable len. Print the value of len as output.
Find Length of String without using strlen() Function
This program does not uses strlen() function to find the length, rather length gets calculated manually here:
#include<stdio.h> #include<conio.h> int main() { char ch[20]; int count=0, i; printf("Enter any string: "); scanf("%s", ch); for(i=0; ch[i]!='\0'; i++) count++; printf("\nLength of the String = %d", count); getch(); return 0; }
Here is its sample run:
Supply any string input say codescracker and press ENTER key to see its length as output:
As in above program, the string was received from the user using scanf() function. Therefore whenever user will provide any string that contains spaces, then only first word will be received and rest gets skipped. Here is the sample run where user entered any string that contains space say codes cracker:
As you can see, the word before space is codes, therefore the program will only calculate the length of codes that will be 5. To solve this problem, we have to use gets() function in place of scanf() to receive the string (along with spaces) from user as shown in the program given below:
#include<stdio.h> #include<conio.h> int main() { char str[100]; int count=0, i; printf("Enter any string: "); gets(str); for(i=0; str[i]!='\0'; i++) count++; printf("\nLength of the String = %d", count); getch(); return 0; }
Here is the final snapshot of the first sample run:
Now let's take another sample run where user enters the string that contains space say codes cracker. Here is the final snapshot of the second sample run:
Program Explained
- Receive any string as input using gets() function
- Use for loop to start from the first character of the string to the last
- If the null terminated character ('\0') occurs, it means nothing left inside the string
- Therefore, until the null terminated character comes, increase the value of count variable each and every time the program flow goes inside the for loop
- The count variable is initialized to 0 at beginning of the program
- Therefore, from first character to the last character of the string, the count variable will be incremented each and every time
- It means, count variable at last, will holds the length of the string, that is how many character present inside the string say str
- Finally print the value of count that shows the length of the string
Find String Length using User-defined Function
This program is made using user-defined function to do the same job as of previous one:
#include<stdio.h> #include<conio.h> int findStringLen(char str[50]); int main() { char str[50]; int len; printf("Enter any string: "); gets(str); len = findStringLen(str); printf("\nLength of the String = %d", len); getch(); return 0; } int findStringLen(char s[50]) { int i, count=0; for(i=0; s[i]!='\0'; i++) count++; return count; }
Here is the final snapshot of the sample run:
Same Program in Other Languages
« Previous Program Next Program »