#include<stdio.h>
int main()
{
	int a, b, c;
	scanf("%d %d %d", &a, &b, &c);
	int i, j, k;
	int ans = -1;
	for (i = 0; i <= a; i++)
		for (j = 0; j <= b; j++)
			for (k = 1; k <= i + 10 * j; k++)
				if (a + b - i - j + (i + 10 * j - k) / 10 + (i + 10 * j - k) % 10 == c)
					if (ans<0 || ans>k)
						ans = k;
	if (ans < 0)
		printf("Impossible\n");
	else
		printf("%d\n", ans);
	return 0;
}