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Discussion of Problem 1118. Nontrivial Numbers

What can be the reason of WA 11? I'll be glad if you give some tests.
Posted by D4nick 31 Mar 2020 08:11
#include <iostream>
using namespace std;
int main() {
    long long i, j, iDel; long long biggestV = 9999999, biggestDel = 9999999;
    cin >> i >> j;
    if (i == 1) {
        cout << 1;
        return 0;
    }
    else if (i == j) {
        cout << i;
        return 0;
    }
    else if (i + 1 == j) {
        cout << (j % 2 != 0 ? j : i);
        return 0;
    }
    for (long long iV = j % 2 != 0 ? j : j-1; iV >= i; iV -= 2) {
        for (iDel = j / 3 + 1; iDel >= 1; iDel--) {
            if (iV%iDel == 0) {
                if (iDel < biggestDel) {
                    biggestDel = iDel;
                    biggestV = iV;
                }
                break;
            }
        }
        if (iDel == 1) {
            cout << iV;
            return 0;
        }
    }
    cout << biggestV;
}
Re: What can be the reason of WA 11? I'll be glad if you give some tests.
Posted by ToadMonster 31 Mar 2020 14:10
In the main cycle you doesn't compare trivialities, you search the smallest biggest divisor in the weird range instead. Could you please show the mathematical proof of your main cycle?

Edited by author 31.03.2020 14:11

Edited by author 31.03.2020 14:12