Question

se citeste un vector de numere intregi ,pozitive cu cel putin 2 cifre fiecare.sa se determine cea mail lunga subsecventa de elemente prime,ale caror inverse sunt tot prime ? hri ma puteti ajuta va rog :)

Answer 1

#include <bits/stdc++.h>
using namespace std;
int n,a[1005];
inline int Prime(int x)
{
    int i;
    if(x<=1)return 0;
    if(x==2)return 1;
    if(x%2==0)return 0;
    for(i=3;i*i<=x;i++)
        if(x%i==0)return 0;
    return 1;
}
inline int Invers(int x)
{
    int numar=0;
    while(x!=0)
    {
        numar=numar*10+x%10;
        x/=10;
    }
    return numar;
}
int main()
{
    int i,s,maxim;
    cin>>n;
    for(i=1;i<=n;i++)
        cin>>a[i];
    s=1;
    maxim=0;
    for(i=2;i<=n;i++)
    {
        if(Prime(a[i])==1 and Prime(Invers(a[i]))==1 and Prime(a[i-1])==1 and Prime(Invers(a[i-1]))==1)
            s++;
        else s=1;
        maxim=max(maxim,s);
    }
    cout<<maxim<<"\n";
    return 0;
}