// yukicoder: No.634 硬貨の枚数1
// 2019.5.1 bal4u

#include <stdio.h>

#define KMAX 4471  // 4471*4472/2 = 9997156
int t[KMAX+5], sz;

int bsch(int x)
{
	int m, l = 0, r = sz;

    while (l < r) {
        m = (l + r) >> 1;
		if (t[m] == x) return 1;
        if (t[m] < x) l = m + 1; else r = m;
    }
	return 0;
}

int main()
{
	int a, k, N;
	
	scanf("%d", &N);
	sz = 0, k = 0, a = 0;
	while (1) {
		a += ++k;
		if (a == N) { puts("1"); return 0; }
		if (a > N) break;
		t[sz++] = a;
	}
	
	a = N >> 1;
	for (k = 0; t[k] <= a; k++) {
		if (bsch(N-t[k])) { puts("2"); return 0; }
	}
	puts("3");
	return 0;
}