比赛的 GG 不以自己的意志为转移。
kal0rona
A – 洗衣服
哇擦,这题 GG 了真的可惜。发现这两个时间独立,那么久分别进行模拟,然后就按均衡的方式分配,然后没了。
// A.cpp #include <bits/stdc++.h> using namespace std; const int MAX_N = 1e5 + 200; typedef long long ll; typedef pair<ll, ll> pii; ll L, n, m, wi[MAX_N], di[MAX_N]; struct node { ll x, y; node() {} node(ll x_, ll y_) : x(x_), y(y_) {} bool operator<(const node &rhs) const { return x > rhs.x || (x == rhs.x && y > rhs.y); } }; priority_queue<node> pq; ll ai[MAX_N * 10], bi[MAX_N * 10]; void fileIO() { freopen("laundry.in", "r", stdin); freopen("laundry.out", "w", stdout); } int main() { fileIO(); scanf("%lld%lld%lld", &L, &n, &m); for (int i = 1; i <= n; i++) scanf("%lld", &wi[i]), pq.push(node(wi[i], wi[i])); for (int i = 1; i <= m; i++) scanf("%lld", &di[i]); // process for wi; for (ll i = 1, x, y; i <= L; i++) { x = pq.top().x, y = pq.top().y; ai[i] = x; pq.pop(), pq.push(node(ai[i] + y, y)); } while (!pq.empty()) pq.pop(); for (int i = 1; i <= m; i++) pq.push(node(di[i], di[i])); for (ll i = 1, x, y; i <= L; i++) { x = pq.top().x, y = pq.top().y; bi[i] = x; pq.pop(), pq.push(node(bi[i] + y, y)); } ll ans = 0; for (int i = 1; i <= L; i++) ans = max(ans, ai[i] + bi[L - i + 1]); printf("%lld\n", ans); return 0; }
B – 编码
比赛的时候加个东西这玩意就 50 了,血亏。
正解就是把 2SAT 放在 Trie 树上搞,优化思想类似于线段树优化建图。
// B.cpp #include <bits/stdc++.h> using namespace std; const int MAX_N = 3e6 + 200; int n, ch[MAX_N][2], ptot = 1, head[MAX_N << 2], current, sat_tot = 1, dfn[MAX_N << 2], dtot; int low[MAX_N << 2], aff[MAX_N << 2], stk[MAX_N << 2], tail, ncnt; bool inst[MAX_N << 2]; int tag[MAX_N]; string str; vector<string> strVec; bool compare(string &a, string &b) { return a.length() < b.length(); } void fileIO() { freopen("code.in", "r", stdin); freopen("code.out", "w", stdout); } struct edge { int to, nxt; } edges[MAX_N << 1]; void addpath(int src, int dst) { edges[current].to = dst, edges[current].nxt = head[src]; head[src] = current++; } void insert(int id) { int p = 1, fa = 0; for (int i = 0; i < str.length(); i++) { if (ch[p][str[i] - '0'] == 0) ch[p][str[i] - '0'] = ++ptot; p = ch[p][str[i] - '0']; if (tag[p]) fa = tag[p]; } sat_tot += 2, addpath(id, sat_tot), addpath(sat_tot ^ 1, id ^ 1); if (fa) { addpath(fa, sat_tot), addpath(sat_tot ^ 1, fa ^ 1); addpath(fa, id ^ 1), addpath(id, fa ^ 1); } tag[p] = sat_tot; } void tarjan(int u) { dfn[u] = low[u] = ++dtot, inst[u] = true, stk[++tail] = u; for (int i = head[u]; i != -1; i = edges[i].nxt) if (dfn[edges[i].to] == 0) tarjan(edges[i].to), low[u] = min(low[u], low[edges[i].to]); else if (inst[edges[i].to]) low[u] = min(low[u], dfn[edges[i].to]); if (dfn[u] == low[u]) { ncnt++; do { aff[stk[tail]] = ncnt, inst[stk[tail]] = false; } while (stk[tail--] != u); } } int main() { fileIO(); memset(head, -1, sizeof(head)); scanf("%d", &n); for (int i = 1; i <= n; i++) cin >> str, strVec.push_back(str); sort(strVec.begin(), strVec.end(), compare); for (int i = 1; i <= n; i++) { bool flag = false; str = strVec[i - 1], sat_tot += 2; int pt = sat_tot; for (int ptr = 0; ptr < str.length(); ptr++) if (str[ptr] == '?') { flag = true; str[ptr] = '0', insert(pt - 1); str[ptr] = '1', insert(pt); break; } if (!flag) insert(pt), addpath(pt - 1, pt); } for (int i = 2; i <= sat_tot; i++) if (dfn[i] == 0) tarjan(i); for (int i = 2; i <= sat_tot; i += 2) if (aff[i] == aff[i + 1]) puts("NO"), exit(0); puts("YES"); return 0; }
C – 猜数列
真的难,不改不改。