座標圧縮ライブラリ

conv.cpp

class Conv {
    ll cursor = 0;
    map<ll, ll> to_short; // <original, small >
    map<ll, ll> to_long; // <small, original>
    std::set<ll> tmp;

    bool build_end = false;

    void set(ll original) {
        if (to_short.find(original) != to_short.end()) {
            return;
        }
        to_long[cursor] = original;
        to_short[original] = cursor;
        cursor++;
    }

public:


    ll revert(ll after) {
        assert(build_end);
        assert(to_long.find(after) != to_long.end());
        return to_long[after];
    }

    ll convert(ll original) {
        assert(build_end);
        assert(to_short.find(original) != to_short.end());
        return to_short[original];
    }

    ll next() {
        return cursor;
    }

    // 前計算省略のため
    void cache(ll t) {
        assert(!build_end);
        tmp.insert(t);
    }

    void build() {
        assert(!build_end);
        for (ll t : tmp) {
            set(t);
        }
    }

};