/* backAndForth.c
 * CS201 - by RA
 */

#include <stdio.h>
int main(void)
{ 
int sum, currentVal;

sum = 0;
currentVal = 1;

while (currentVal <= 100) {
   sum = sum + currentVal;
   currentVal = currentVal + 1;
   }

printf("\nSum is %d\n", sum);

sum = 0;
currentVal = 100;

while (currentVal > 0) {
   sum = sum + currentVal;
   currentVal = currentVal - 1;
   }
printf("Sum is %d\n", sum);


for (sum=0, currentVal=1; 
	currentVal <= 100; 
	   sum += currentVal, currentVal ++);
printf("\nSum is %d\n", sum);

for (sum=0, currentVal=100; 
	currentVal >0; 
	   sum += currentVal, currentVal --);
printf("Sum is %d\n\n", sum);



for (sum=0, currentVal=1; 
	currentVal <= 100; 
	   sum += currentVal, ++currentVal);
printf("\nSum is %d\n", sum);


for (sum=0, currentVal=100; 
	currentVal >0; 
	   sum += currentVal, --currentVal);
printf("Sum is %d\n\n", sum);

for (sum=0, currentVal=-100; 
	currentVal >0; 
	   sum += currentVal, currentVal *= -2);
printf("Sum is %d\n\n", sum);


//for (sum=0, currentVal=-100; ; currentVal >0, sum += currentVal, currentVal *= -2);

/* for (sum=0, currentVal=-100;; 	currentVal >0, 
	currentVal *= -2) 
	sum += 	currentVal;
*/

sum = 0;

for (currentVal = -100; 
	 currentVal > -200; 
	 currentVal += -2) 
		sum += 	currentVal;

printf("Sum is %d\n\n", sum);

for (currentVal = -100;; 
	 currentVal > -200, 
	 currentVal += -2) 
		sum += 	currentVal;



exit(0);
}