#include <stdio.h>
#include <stdlib.h>
void addsum(void);
 
int main(void)
{
    addsum(); 
    system("pause");
    return 0;
    }
void addsum(void)
{
  int sum;   
  sum=((1+100)*100)/2;
  printf("sum=%d\n",sum);
  }

#include <stdio.h>
#include <stdlib.h>
int answer(int);

int main(void)
{

printf("sum=%d\n",answer(100));

system("pause");
return 0;
}
int answer(int x)
{
if ( x == 1 )
 return 1;
else 
return x + answer(x - 1);
}   

int AddSum(int Num)
{
    static int Sum = 0;
    Sum = Sum + Num;
    return Sum;
}

#include <stdio.h>
#include <stdlib.h>
int addsum(int);

int main(void)
{
  int i,sum;
  for(i=1;i<=100;i++)
   addsum(i);
  printf("%d\n",addsum(sum)); 
  system("pause");
  return 0;
  
}
int addsum(int i)
{
  static int Sum = 0;
  Sum = Sum + i;
  return Sum;
}