This C Cheatsheet is For You!
  1. C

    2. Basic syntax and functions from the C programming language.

  2. Boilerplate Code
    3. #include <stdio.h>
int main()
{
return(0);
}
  3. printf function

    4. It is used to show output on the screen

    printf("Hello Kashmir!");
  4. scanf

    5. It is used to take input from the user

    scanf("placeholder", variables)
  5. Comments

    6. A comment is the code that is not executed by the compiler, and the programmer uses it to keep track of the code. 

    // It's a single line comment
/* It's a 
multi-line
comment
*/
  6. Data types

    7. The data type is the type of data

    Typically a single octet(one byte). It is an integer type
char variable_name;
int variable_name;
A single-precision floating-point value
float variable_name;
A double-precision floating-point value
double variable_name;
  7. Void type

    8. Represents the absence of the type

    Void
  8. Alarm or Beep,Backspace,Newline,Tab,Single quote
    9. \a
\b
\n
\t
\''
  9. Conditional Instructions

    10. Conditional statements are used to perform operations based on some condition. 

    if (/* condition */)
{
/* code */
}
  10. if-else statement
    11. if (/* condition */)
{
/* code */
}
else{
/* Code */
}
  11. if else-if Statement
    12. if (condition) {
// Statements;
}
else if (condition){
// Statements;
}
else{
// Statements
}
  12. Switch Case Statement

    13. It allows a variable to be tested for equality against a list of values (cases). 

    switch (expression) 
{
case constant-expression: 
statement1;
statement2;
break;
case constant-expression: 
statement;
break;
...
default: 
statement;
}
  13. Loops

    14. Iterative statements facilitate programmers to execute any block of code lines repeatedly and can be controlled as per conditions added by the programmer. 

    while (/* condition */)
{
/* code */
}
  14. do-while loop
    15. do
{
/* code */
} while (/* condition */);
  15. For loop
    16. for (int i = 0; i < count; i++)
{
/* code */
}
  16. Break Statement,Continue Statement

    17. break keyword inside the loop is used to terminate the loop

    continue keyword skips the rest of the current iteration of the loop and returns to the starting point of the loop 

    break;
continue;
  17. Functions & Recursion

    18. Functions are used to divide an extensive program into smaller pieces. It can be called multiple times to provide reusability and modularity to the C program. 

    return_type function_name(data_type parameter...){ 
    //code to be executed 
    }
  18. Recursion
    19. void recurse()
{
... .. ...
recurse();
... .. ...
}
  19. Pointers

    20. Pointer is a variable that contains the address of another variable, 

    Declaration
datatype *var_name;
  20. Arrays

    21. An array is a collection of data items of the same type.

    data_type array_name[array_size];
  21. Strings,gets() function,puts("string");

    22. A string is a 1-D character array terminated by a null character ('\0')

    It allows you to enter multi-word string

    It is used to show string output

    char str_name[size];
gets("string");
puts("string");
  22. String Functions
    23. strlen(string_name);
It is used to calculate the length of the string
strcpy(destination, source);
It is used to copy the content of second-string into the first string passed to it
strcat(first_string, second_string);
It is used to concatenate two strings
strcmp(first_string, second_string);
It is used to compare two strings
  23. Structures

    24. The structure is a collection of variables of different types under a single name. Defining structure means creating a new data type. 

    struct structureName 
{
dataType member1;
dataType member2;
...
};