String: Write a c program to convert the string from lower case to upper case

Convert String from lowercase to uppercase 

#include<stdio.h>
#include<string.h>
int main()
{
  char str[50];
  int i,b=0;
  printf("Enter lowercase word: ");
  scanf("%s",str);
  b=strlen(str);
  for(i=0;i<=b;i++)
    {
        if(str[i]>=97&&str[i]<=122)
        str[i]=str[i]-32;
  }
  printf("\nThe string in Uppercase is:%s",str);
  return 0;
}