cs202xy login: _____________________________________________

1. Write C code for a program that does the following.

Take one integer from the command-line arguments; call the integer n.

Ask the user to enter an integer n times.  After each time the user
types an integer, display the partial sum of all the integers typed
so far.  Whenever the partial sum increases by more than a /factor of
2/, also print "Woah big fella."

Here is a sample transcript...

./myProgram 4
Type an integer: 3
  partial sum: 3
  Woah big fella.
Type an integer: 2
  partial sum: 5
Type an integer: 2
  partial sum: 7
Type an integer: 8
  partial sum: 15
  Woah big fella.

Grading: 2 points total.
* 2/2 - correct except for perhaps one tiny syntax error
* 1.5/2 - ...
* 1/2 - at least one part correct (command-line arg to int, loop n times, computing sum) and nothing ridiculous
* 0/2 - 


Common mistakes
* note that argc is # of arguments, not the argument.  In the example argc is 2
* note that argv[1] is a char *, so atoi(argv[1]) is the 4.
* for scanf and an integer you do scanf("%d", & variableName);
* for char s[100], you can do scanf("%s", s);
* checking if increase by factor of 2, something like
  if (newSum > 2 * oldSum) ...





















2. Play Computer.  Keep track of the values of all the variables 
and what is printed on the screen.
/*
	Final output from this:
	h-e-l-l-o
	iemlp

	Final output if we remove that mistake line:
	h-e-l-l-o
	ifmmp
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

char s[10] = "hello";

void fun(char *s) {
  if (!*s) return;

  (*s)++;
  s++; // note: this was a mistake on my part.

  fun(s+1);
}

int main(int argc, char *argv[]) {

  int i;
  for(i=0; s[i] != '\0'; i++) {
    printf("%c-", s[i]);
  }
  printf("\n");

  fun(s);
  printf("%s\n", s);
  
  
  return 0;
}


Grading: 2 points total
* 2/2 - correct except for perhaps one tiny mistake
* 1.5 - one modest mistake (e.g., having h-e-l-l-o instead of h-e-l-l-o-)
* 1/2 - some parts correct (e.g., got h-e-l-l-o- part correct), nothing ridiculous
* 0/2 - no part correct