Character conversion function and digital conversion function _c language in C language standard library

Convert character to number:

#include <stdlib.h>

Atoi (); Converts a character to an integer example: Char ch1;int i=atoi (CH1);

ATOL () converts a character to a long integer example: Char ch2;long l=atol (CH2);

Atof () converts a character to a floating-point example: Char ch3;float f=atof (CH3);

Strtod (); Converts a string to a Double-precision type example: String str1;double d=strtod (STR1);

Strtol (); Converts a string to a long integer example: string str2; Long int li=strtol (STR2);

Strtoul (); Converts a string into a no-length integer example: Sting str3; unsinged long int uli=str (STR3);

Convert numbers to characters:

Itoa (); Converts an integer to a character
Example: int i; Char ch1; Itoa (I,ch1,radix);
Radix is base: Want to convert ch1 to decimal is 10, octal is 8, hexadecimal is 16

Ltoa (); Converts a long integer to a character example: Long int i li; Char CH2; Ltoa (Li,ch2,radix);

Ultoa (); Converts a no-length integer to a character example: unsiged long int uli; Char CH3; Ultoa (Uli,ch3,radix);

Conversion of characters and characters:

#include <ctype.h>

ToLower (); Converts an uppercase letter to a lowercase letter
Example: Char upper=c; Char Lower=tolower (upper);//Get Lower=c

ToUpper (); Converts one by one lowercase letters to uppercase letters
Example: Char lower=c; Char Upper=toupper (lower);//Get Upper=c