問題 やりかた 以下ソース。 class ArithmeticProgressions { public: ll N, m, M; vector<ll> s; ll floor(ll a, ll b){ ll m = a % b; if(m < 0) m += b; return (a - m) / b; } ll ceil(ll a, ll b){ ll m = a % b; if(m < 0) m += b; if(m > 0) m = b - m; r</ll>…