PRIME1195 C++

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

int minn,s=0,m,n;
bool ktnt(int x)
{
    if (x<2) return false;
    if (x==2) return true;
    for (int i=2;i<=int(sqrt(x));i++)
        if (x%i==0) return false;
    return true;
}

void giai()
{
    minn=100000000;
    if(m==1)
    {
        cout<<-1;return;
    }
    for(int i=1;i<=int(sqrt(m));i++)
    {
        if(m%i==0)
        {
            if(ktnt(i)==true)
                if(abs(i-n)<minn)
                    minn=abs(i-n);
            if(ktnt(m/i)==true)
                if(abs(m/i-n)<minn)
                    minn=abs(m/i-n);
        }
    }
    //cout<<(n-minn);
    if(ktnt(n-minn)==true&&m%(n-minn)==0)
        cout<<(n-minn);
    if(ktnt(n+minn)==true&&m%(n+minn)==0)
        cout<<" "<<(n+minn);
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    freopen("prime1195.inp","r",stdin);
    freopen("prime1195.out","w",stdout);
    cin>>m>>n;
    giai();
}