Write a c program to calculate reverse string and length string help with library function

Program:

#include<stdio.h>
#include<conio.h>
#include<string.h>
void main()
{
char str[100];
int i;
printf("Enter the string: ");
scanf("%s",str);
printf("Reverse of  str is %s\n",strrev](str));
printf("length of sting is %d",strlen(str));
getch();
}

Output:

Enter the string: Aryan
Reverse of str is nayrA
length of string is 5