Second Largest Number

Problem Statement
Write a c program to calculate second largest number from entered number,
you should not use any array to store these numbers
#include<stdio.h>
int main()
{
  int flag,input,max,secmax;
  printf("enter the numbers resp. enter ctrl-d in the end ");
  flag=1;
  while(scanf("%d",&input)!=EOF)
    {
      if(flag==1)
    {
      max=input;
      secmax=input;
      flag++;
    }
      if(input>max)
    {
      secmax=max;
      max=input;
    }
      else if(input>secmax)
    {
      secmax=input;
    }
    }
  printf("the secound maximum input entered is %d \n",secmax);
  return 0;
}