Course
Introduction
C "Hello, World!" ProgramPrint an Integer (Entered by the User)Add Two IntegersMultiply Two Floating-Point NumbersFind ASCII Value of a CharacterCompute Quotient and RemainderFind the Size of int, float, double and charSwap Two NumbersDecision Making and Loops
Check Whether a Number is Even or OddCheck Whether a Character is a Vowel or ConsonantFind the Largest Number Among Three NumbersFind the Roots of a Quadratic EquationCheck Leap YearCheck Whether a Number is Positive or NegativeCheck Whether a Character is an Alphabet or notCalculate the Sum of Natural NumbersFind Factorial of a NumberGenerate Multiplication TableDisplay Fibonacci SequenceFind GCD of two NumbersFind LCM of two NumbersDisplay Characters from A to Z Using LoopCount Number of Digits in an IntegerReverse a NumberCalculate the Power of a NumberCheck Whether a Number is Palindrome or NotCheck Whether a Number is Prime or NotDisplay Prime Numbers Between Two IntervalsCheck Armstrong NumberDisplay Armstrong Number Between Two IntervalsDisplay Factors of a NumberMake a Simple Calculator Using switch...casePrint Pyramids and PatternsFunctions
Demonstrate the Working of Keyword longDisplay Prime Numbers Between Intervals Using FunctionCheck Prime or Armstrong Number Using User-defined FunctionCheck Whether a Number can be Expressed as Sum of Two Prime NumbersFind the Sum of Natural Numbers using RecursionFind Factorial of a Number Using RecursionFind G.C.D Using RecursionConvert Binary Number to Decimal and vice-versaConvert Octal Number to Decimal and vice-versaConvert Binary Number to Octal and vice-versaReverse a Sentence Using Recursioncalculate the power using recursionArrays and Pointers
Calculate Average Using ArraysFind Largest Element in an ArrayCalculate Standard DeviationAdd Two Matrices Using Multi-dimensional ArraysMultiply Two Matrices Using Multi-dimensional ArraysFind Transpose of a MatrixMultiply two Matrices by Passing Matrix to a FunctionAccess Array Elements Using PointerC Program Swap Numbers in Cyclic Order Using Call by ReferenceFind Largest Number Using Dynamic Memory AllocationStrings
Find the Frequency of Characters in a StringCount the Number of Vowels, Consonants and so onRemove all Characters in a String Except AlphabetsFind the Length of a StringConcatenate Two StringsCopy String Without Using strcpy()Sort Elements in Lexicographical Order (Dictionary Order)Structures and Unions
Store Information of a Student Using StructureAdd Two Distances (in inch-feet system) using StructuresAdd Two Complex Numbers by Passing Structure to a FunctionCalculate Difference Between Two Time PeriodsStore Information of Students Using StructureStore Data in Structures DynamicallyC Program to Remove all Characters in a String Except Alphabets
To understand this example, you should have the knowledge of the following C programming topics:
Remove Characters in String Except Alphabets
#include <stdio.h>
int main() {
char line[150];
printf("Enter a string: ");
fgets(line, sizeof(line), stdin); // take input
for (int i = 0, j; line[i] != '\0'; ++i) {
// enter the loop if the character is not an alphabet
// and not the null character
while (!(line[i] >= 'a' && line[i] <= 'z') && !(line[i] >= 'A' && line[i] <= 'Z') && !(line[i] == '\0')) {
for (j = i; line[j] != '\0'; ++j) {
// if jth element of line is not an alphabet,
// assign the value of (j+1)th element to the jth element
line[j] = line[j + 1];
}
line[j] = '\0';
}
}
printf("Output String: ");
puts(line);
return 0;
}
Output
Enter a string: p2'r-o@gram84iz./
Output String: programiz
This program takes a string input from the user and stores in the line variable. Then, a for loop is used to iterate over characters of the string.
If the character in a string is not an alphabet, it is removed from the string and the position of the remaining characters are shifted to the left by 1 position.