#include <stdio.h>
#include <ctype.h>
#include <string.h>

// Function to compare two strings ignoring case
int compareStringsIgnoreCase(const char* str1, const char* str2) {
    while (*str1 != '\0' && *str2 != '\0')
    {
        // Convert both characters to lowercase and compare
        if (tolower((unsigned char)*str1) != tolower((unsigned char)*str2)) {
            return 0; // Strings are not equal
        }
        str1++;
        str2++;
    }

    // Check if both strings have ended
    return 1;
}

int main() {
    char str1[100], str2[100];

    // Prompt user to enter the first string
    printf("Enter the first string: \n");
    // scanf("%[^\n]%*c", str1);
  fgets(str1, sizeof(str1), stdin);

    // Prompt user to enter the second string
    printf("Enter the second string: \n");
        // scanf("%[^\n]%*c", str2);

    fgets(str2, sizeof(str2), stdin);

    // Remove the newline character from fgets input
    str1[strcspn(str1, "\n")] = '\0';
    str2[strcspn(str2, "\n")] = '\0';

    // Compare the strings ignoring case
    if (compareStringsIgnoreCase(str1, str2)) {
        printf("The strings are equal (ignoring case).\n");
    } else {
        printf("The strings are not equal.\n");
    }

    return 0;
}
by

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Read inputs from stdin

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#include <stdio.h>
int main()
{
    char name[50];
    printf("Enter name:");
    scanf("%s", name);
    printf("Hello %s \n" , name );
    return 0;
    
}

About C

C language is one of the most popular general-purpose programming language developed by Dennis Ritchie at Bell laboratories for UNIX operating system. The initial release of C Language was in the year 1972. Most of the desktop operating systems are written in C Language.

Key features:

  • Structured Programming
  • Popular system programming language
  • UNIX, MySQL and Oracle are completely written in C.
  • Supports variety of platforms
  • Efficient and also handle low-level activities.
  • As fast as assembly language and hence used as system development language.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition if-else is used.

if(conditional-expression) {
   // code
} else {
   // code
}

You can also use if-else for nested Ifs and if-else-if ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to if-else-if ladder.

switch(conditional-expression) {    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
...    
    
default:     
 // code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  // code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while(condition) {  
 // code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {
  // code 
} while (condition);

Arrays

Array is a collection of similar data which is stored in continuous memory addresses. Array values can be fetched using index. Index starts from 0 to size-1.

Syntax

One dimentional Array:

data-type array-name[size];

Two dimensional array:

data-type array-name[size][size];

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity.

Two types of functions are present in C

  1. Library Functions:

Library functions are the in-built functions which are declared in header files like printf(),scanf(),puts(),gets() etc.,

  1. User defined functions:

User defined functions are the ones which are written by the programmer based on the requirement.

How to declare a Function

return_type function_name(parameters);

How to call a Function

function_name (parameters)

How to define a Function

return_type function_name(parameters) {  
  //code
}