#include<stdio.h>
longlong a[100010];
int main(){int n;scanf("%d",&n);for(int i=0;i<n;i++)scanf("%lld",&a[i]);int zero=0;
for(int i=0;i<n;i++)if(a[i]==0)zero++;if(zero >0){printf("0\n");return 0;}long long prod=1;for(inti=0;i<n;i++){if(a[i]<=1000000000000000000/prod){prod*=a[i];}else{printf("-1\n");return 0;}}printf("%lld\n",prod);}