C++ Program .Write a program to calculate length of string using standard library function.

#include<stdio.h>
#include<conio.h>
#include<string.h>
void main()
{
char str[100];
int length;
clrscr();
printf("\n Enter The String:-");
gets(str);
length=strlen(str);

/*i=0;
while(str[i]!='\0')
{
i++;
} */
printf("\n The lenght of string is:- %d",length);
getch();
}