Please read the instruction very carefully. Do not use Atoi or parseint to parse the string. Thank you in advance. Your help is appreciated

#include #include stdbool.h> * The isinteger) function examines the string given as its first argument, and returns true if and only if the string representsa optional leading followed by one or more decimal digits. Returns true if the given string represents an integer, false * well-formed integer. A well-formed integer consists only of an otherwise. bool isinteger(char *str) The parseint) function parses a well-formed string representation of k an integer (one which would return true from isinteger()) and returns the integer value represented by the string. For example, the string "1234" would return the value 1234. This function does not need to * handle badly-formed strings in any particular fashion, its operation on badly-formed strings is undefined. Returns the integer value stored in the given string int parseint(char *str); The main function is where C programs begin This function parses its arguments and returns the value they represent. Its arguments are either: A single argument representing an integer Three arguments, where the first and third are integers and the second is an operator to be performed on those integers * Remember that the argument in argv[0] is the name of the program, so * a program passed exactly one argument on the command line will * receive_two arguments: its name in argv [0] and the provided * argument in argv[1]. Arguments: argc- The number of arguments received argv - The arguments received as an array of C strings Returns if the arguments are well-formed and the calculation could be performed, non-zero otherwise. int main(int argc, char argv[]) /* Your main program logic should go here, with helper logic in the * functions isinteger) and parseint), which you can place below * the closing brace of main) return 0