What is an Identifier and keyword? Explain the rules for naming valid identifiers in C with example.Write a C program to find sum of digits of a 'n' digit number.[5+5]

An identifier is a name given to various program elements such as variables, functions, arrays, structures, and other user-defined items. Identifiers are used to uniquely identify a program element during execution. Example: --- A keyword is a reserved word that has a predefined meaning in the C ...