View Code of Problem 73

#include<stdio.h>
int main()
{
  int N,day,sum;
  day=1,sum=1;
  scanf("%d",&N);
  while(day<N)
  {
    sum=(sum+1)*2;
    day++;
  }
  printf("%d",x1);
  return 0;
}
  
/*
Main.c: In function 'main':
Main.c:12:15: error: 'x1' undeclared (first use in this function)
   printf("%d",x1);
               ^
Main.c:12:15: note: each undeclared identifier is reported only once for each function it appears in
*/