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#include<bits/stdc++.h>
using namespace std;

int n; 
int ile = 0;

int main() {
	scanf("%d",&n);
	for(int i = 1; i <= n; ++i) {
		int x; scanf("%d",&x);
		if(x == 1) ile++;
	}
	
	if(ile >= 2) {
		printf("0\n");
	}
	else if(ile == 1) {
		printf("1\n");
	}
	else {
		printf("2\n");
	}
	
	printf("2\n");
	printf("1 2\n");
}