题目link

思路

思维题
发现 m 与 0 交错出现值最大

signed main()
{
    int n,m;cin>>n>>m;
    cout << n*(n-1)/2*m << endl;
    int f = 0;
    forr(i,1,n){
        if(!f) cout << m << " ",f = 1;
        else cout << 0 << " ",f = 0;
    }
    return 0;
}