#include <stdio.h>

#include <math.h>


int main()

{

int i, n, sum;

i = 0;

sum = 0;

do

{

i++

sum += i;

} while (sum < 10000);

printf(" sum from 1 to %d = %d ", i-1, sum-i);

printf(" sum from 1 to %d = %d ", i, sum);

printf(" answer %d", i);

return 0;


}