Learn To Solve It

This is a companion website to learn C programming using K&R book. It uses modern tools, and is designed to be used along with the book.

I recommend https://exercism.org as the platform to learn Programming and practice with a dedicated community.

Reference Books

• C Programming Language by Kernighan and Ritchie.

C Programming

• A Tutorial Introduction
  • 1.1 Getting Started
  • 1.1 testing hello, world
  • 1.2 Variables and Arithmetic Expressions
  • 1.3 The for statement
  • 1.3 Temperature Convertor
  • 1.4 Symbolic Constants
  • 1.4 Temperature Convertor
  • 1.5.1 File Copying
  • 1.5.2 Character Counting
  • 1.5.2 Character Counting2
  • 1.5.3 Line Counting
  • 1.5.4 Word Counting
  • 1.5 Character Input and Output
  • 1.5 Temperature Convertor in Reverse
  • 1.6 Arrays
  • 1.6 Verify the value of EOF
  • 1.7 Functions
  • 1.7 Value of EOF
  • 1.8 Count blanks, tabs and newlines
  • 1.9 Character Arrays
  • 1.9 Replace Continous blanks with a single blank
  • 1.10 External Variables and Scope
  • 1.10 Explicit Tabs, Backslash and Backspaces
  • 1.11 Test Word count program
  • 1.13.2 Vertical Histogram
  • 1.13 Horizontal Histogram
  • 1.14 Histogram of Frequency of Characters
  • 1.15 Temperature Convertor using function call
  • 1.16 Print length of arbitrary long input line
  • 1.17 Print lines that are longer than 80 chars
  • 1.18 Remove trailing blanks and tabs
  • 1.19 reverse a string
  • 1.20 detab, replaces tabs with spaces
  • 1.21 entab, replaces spaces with tabs
  • 1.22 fold long lines
  • 1.23 Remove comments from a C program
  • 1.24 Check rudimentary Syntax Errors in a C Program
• Types, Operators and Expressions
  • 2.1 Count the Ranges
  • 2.2 Write getline without && and || operator
  • 2.3 Converting Hexadecimal Digits Into Integers
  • 2.4 Compare S1, S2 To Delete Same Character in S1
  • 2.5 return the first location in the string s1 comparing s2
  • 2.6 Setting bits at a position n
  • 2.7 Setting bits at a position n Inverted
  • 2.8 returns the value of the integer x rotated to the right by n positions
  • 2.9 two’s complement number system
  • 2.10 upper case letters to lower case
• Control Flow
  • 3.1 Binsearch function, writing minimum tests inside a loop
  • 3.2 escape sequences into the real characters
  • 3.3 expand short hand notation in s1 into string s2
  • 3.4 itoa to handle largest negative integer
  • 3.5 function itob, converts a integer into a string
  • 3.6 itoa with field width
• Functions and Program Structure
  • 4.1 strindex which returns rightmost occurance
  • 4.2 Extend atof to handle scientific notation
  • 4.3 RPN modulus operator and negative numbers
  • 4.4 RPN Calculator - print two top elements of the stack without popping
  • 4.5 RPN Calculator with mathematical functions
  • 4.6 RPN Calculator with variables
  • 4.7 Function ungets that will push back an entire string onto the input
  • 4.8 getch and ungetch handling pushback character
  • 4.9 getch and ungetch handling EOF Character
  • 4.10 Calculator using getline
  • 4.11 getline using static
  • 4.12 convert integer into string by calling recursive routine
  • 4.13 reverse the string s
  • 4.14 swap that interchanges two arguments of type t
• Pointers and Arrays
  • 5.1 get next integer from input to *pn
  • 5.2 get next float from input to *pn
  • 5.3 strcat(s,t) copies the string t to the end of s
  • 5.4 strend returns 1 if string t occurs at the end of the string s
  • 5.5 simple versions of strncpy, strncat, and strncmp
  • 5.6 Find the pattern using pointers
  • 5.7 Readlines using array
  • 5.8 program which has day of the year and month day
  • 5.10 expr, evaluate rpn from command line
  • 5.11 entab and detab which accepts arguments
  • 5.12 entab -m + which accepts arguments
  • 5.13 tail prints the last n lines of input
  • 5.14 sorting in reverse (decreasing) order
  • 5.15 fold upper and lower case together
  • 5.16 -d makes comparison on letters, numbers, blanks
  • 5.17 Sorting with options
  • 5.18 recover from input errors
  • 5.19 undcl does not add redundant parentheses
  • 5.20 dcl handling declarations with function argument types, qualifiers
• Structures
  • 6.1 getword
  • 6.2 Identical Variables
  • 6.3 Cross Referencer
  • 6.4 Words and Frequency
  • 6.5 undef: remove name and definition from table
  • 6.6 define processor
• Input and Output
  • 7.1 upper case to lower or lower case to upper
  • 7.2 print non-graphic characters in octal or hexadecimal
  • 7.3 minprintf to handle facilities of printf
  • 7.4 private version of scanf
  • 7.5 Postfix calculator using scanf
  • 7.6 Compare Two files
  • 7.7 Pattern matching program with files
  • 7.8 Print Pages to Files
  • 7.9 Analyze implementations of isupper
• The UNIX System Interface
  • 8.1 program cat using read, write, open and close
  • 8.2 Rewrite fopen and _fillbuf with fields
  • 8.3 _flushbuf, fflush and fclose
  • 8.4 implement fseek
  • 8.5 inode entry
  • 8.6 Write calloc, by calling malloc
  • 8.7 Error checking by malloc
  • 8.8 bfree maintained by malloc
  • 8.2 Buffered and Unbuffered getchar
  • 8.2 Read and Write
  • 8.3 open and create calls
• C Programming Building Blocks
  • Integer and float data types
  • Character Datatype
  • Character Array and String
  • Pointers
  • Structures
  • Pointer to Structures
  • TypeDefs
  • DEFS and IFDEFS Macros
  • Union and Pointer to Unions
  • Bitwise manipulation
  • Using extern
  • Using enums
  • malloc and calloc
• C Concepts Visualization
  • Stack Frames and Local Variables
  • Pointer as a Memory Address
  • Array and Pointer Arithmetic
  • String as a Null-Terminated Character Array
  • Pass by Value vs Pass by Reference
  • Linked List and Heap Allocation
  • Recursive Call Stack Unwinding
  • Stack Data Structure: sp Index and val[] Array
  • Struct Memory Layout and Nested Structs
  • Union: Multiple Interpretations of the Same Bytes
  • Static Variable: Persistent Local State
  • Pointer to Pointer: Two Levels of Indirection