#include<stdio.h>
int main(){
    int n;
    scanf("d",&n);
    if(n<0){
        printf("Invalid Input");
        return 0;
    }
    int arr[n];
    int hasNegative =0;
    for(int i=0;i<n;i++){
        scanf("%d",&arr[i]);
        if(arr[i] <0)
           hasNegative =1;
    }
    if(hasNegative){
        printf("Invalid Input");
        return 0;
    }
    int min=101;
    for(int i=0;i<n;i++){
        if(arr[i]>0 && arr[i] <min)
        min =arr[i];
    }
    if(min==101)
       printf("No positive number found");
    else
       printf("%d",min);
    return 0;
}