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C Tutorial

C HOME C Intro C Get Started C Syntax
Syntax Statements Code Challenge
C Output
Print Text New Lines Code Challenge
C Comments C Variables
Create Variables Format Specifiers Change Values Multiple Variables Variable Names Real-Life Examples Code Challenge
C Data Types
Data Types Characters Numbers Decimal Precision Memory Size Real-Life Example Extended Types Code Challenge
C Type Conversion C Constants C Operators
Operators Arithmetic Assignment Comparison Logical Precedence Code Challenge
C Booleans
Booleans Real-Life Examples Code Challenge
C If...Else
if else else if Short Hand If Nested If Logical Operators Real-Life Examples Code Challenge
C Switch
Switch Code Challenge
C While Loop
While Loop Do/While Loop Real-Life Examples Code Challenge
C For Loop
For Loop Nested Loops Real-Life Examples Code Challenge
C Break/Continue C Arrays
Arrays Array Size Array Loops Real-Life Examples Multi-Dim Arrays Code Challenge
C Strings
Strings The Null Character Strings and Loops Special Characters String Functions Character Functions Arrays of Strings Code Challenge
C User Input C Memory Address C Pointers
Pointers Pointers & Arrays Pointer Arithmetic Pointer to Pointer Code Challenge

C Functions

C Functions C Function Parameters C Pass By Reference C Scope C Function Declaration C Functions Challenge C Math Functions C Inline Functions C Recursion C Function Pointers
Function Pointers Callback Functions

C Files

C Create Files C Write To Files C Read Files

C Structures

C Structures C Structs Challenge C Nested Structures C Arrays of Structs C Structs & Pointers C Unions C typedef C Struct Padding

C Enums

C Enums
Enums Code Challenge

C Memory

C Memory Management C Allocate Memory C Access Memory C Reallocate Memory C Deallocate Memory C Structs and Memory C Memory Example C Memory Mistakes

C Errors

C Errors C Error Challenge C Debugging C NULL C Error Handling C Input Validation

C Problem Solving

C Problem Solving C Build the Logic C Edge Cases & Errors C Test Cases

C Projects

C Projects

C More

C Date C Random Numbers C Macros C Organize Code C Storage Classes C Bitwise Operators C Fixed-width Integers C Command-Line Args

C DSA

C DSA Intro C Searching C Sorting C Stacks C Queues C Linked Lists
Linked Lists Insert and Delete
C Trees C Hash Tables C Big O

C Cert

C Certificate

C Examples

C Examples C Real-Life Examples C Exercises C Quiz C Code Challenges C Practice Problems C Compiler C Syllabus C Study Plan C Interview Q&A

C Reference

C Reference C Keywords
auto break case char const continue default do double else enum extern float for goto if inline int long register restrict return short signed sizeof static struct switch typedef union unsigned void volatile while _Alignas _Alignof _Atomic _Bool _Complex _Generic _Imaginary _Noreturn _Static_assert _Thread_local
C Preprocessor C <assert.h>
assert()
C <ctype.h>
isalnum() isalpha() isblank() iscntrl() isdigit() isgraph() islower() isprint() ispunct() isspace() isupper() isxdigit() tolower() toupper()
C <errno.h> C <limits.h> C <math.h>
acos(x) acosh(x) asin(x) asinh(x) atan(x) atan2(y, x) atanh(x) cbrt(x) ceil(x) copysign(x, y) cos(x) cosh(x) exp(x) exp2(x) expm1(x) erf(x) erfc(x) fabs(x) fdim(x, y) floor(x) fma(x, y, z) fmax(x, y) fmin(x, y) fmod(x, y) frexp(x, y) hypot(x, y) ilogb(x) ldexp(x, y) lgamma(x) llrint(x) llround(x) log(x) log10(x) log1p(x) log2(x) logb(x) lrint(x) lround(x) modf(x, y) nan(s) nearbyint(x) nextafter(x, y) nexttoward(x, y) pow(x, y) remainder(x, y) remquo(x, y, z) rint(x) round(x) scalbln(x, y) scalbn(x, y) sin(x) sinh(x) sqrt(x) tan(x) tanh(x) tgamma(x) trunc(x)
C <stdbool.h> C <stddef.h>
offsetof()
C <stdint.h> C <stdio.h>
fclose() fgetc() fgets() fopen() fprintf() fputc() fputs() fread() fscanf() fseek() ftell() fwrite() getchar() printf() putchar() puts() remove() rename() rewind() scanf() snprintf() sprintf() sscanf()
C <stdlib.h>
abs() atof() atoi() atol() atoll() calloc() div() exit() free() malloc() qsort() rand() realloc() srand()
C <string.h>
memchr() memcmp() memcpy() strcat() strchr() strcmp() strcpy() strcspn() strerror() strlen() strncat() strncmp() strncpy() strpbrk() strrchr() strspn() strstr() strtok()
C <time.h>
asctime() clock() ctime() difftime() gmtime() localtime() mktime() strftime() time()


C Reference Documentation

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This section contains a C reference documentation.

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C Reference

A list of C keywords and popular libraries can be found here:

Keywords Preprocessor <assert.h> <ctype.h> <errno.h> <limits.h> <math.h> <stdbool.h> <stddef.h> <stdint.h> <stdio.h> <stdlib.h> <string.h> <time.h>

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