#include <iostream> #include <vector> #include <algorithm> using ll = long long; int answer(std::vector<ll> const &ws, std::vector<ll> const &cs, const ll s, const ll k) { int eaten = 0; ll weight = s; ll wdiff = k - weight; // stack keeps (max_pos (excluded), num_eaten) std::vector<std::pair<ll, ll>> stack = { {0, 0} }; while (wdiff > 0) { auto next_max = std::lower_bound(std::cbegin(ws), std::cend(ws), weight); if (next_max == std::begin(ws)) { // we can't eat any other fish return -1; } auto gain = std::prev(next_max); // how much we need to either achieve k or reach next MAX ll need = wdiff - 1; // let's hope this (-1) with not break everything if (next_max != std::cend(ws)) { need = std::min(*next_max - weight, need); } // let's eat this fish ll dist = std::distance(std::cbegin(ws), next_max); if (stack.back().first + 1 == dist) { // by eating this fish we will use whole range auto [pm, pv] = stack.back(); stack.back() = { dist, pv + 1 }; } else { stack.push_back({ dist, 1 }); } weight += *gain; wdiff -= *gain; need -= *gain; eaten += 1; // let's try achieve next MAX while (need >= 0 && stack.size() >= 2) { auto [cpos, cnum] = stack[stack.size() - 1]; auto [mpos, mnum] = stack[stack.size() - 2]; // optimization: use `cs` to check if we are going to eat whole range ll base = cs[cpos - 1]; auto lim = std::cbegin(cs) + cpos - cnum + 1; auto rng = std::upper_bound(std::cbegin(cs) + mpos + 1, lim, need, [=](auto &&v, auto &&t) { return -v <= -(base - t); }); ll range = std::distance(rng, lim); ll gained = base - *std::prev(rng); need -= gained; weight += gained; wdiff -= gained; eaten += range; if (rng == std::cbegin(cs) + mpos + 1) { // we need to eat whole range // merge both ranges stack.pop_back(); stack.pop_back(); stack.push_back({ cpos, mnum + cpos - mpos }); } else { // update max on stack (we have enough) stack.back().second += range; } } if (need >= 0 && wdiff > 0) { return -1; // we can't advance MAX } if (wdiff <= 0) { break; } } return eaten; } int main() { std::ios::sync_with_stdio(false); int n; std::cin >> n; std::vector<ll> ws(n); std::vector<ll> cs(n + 1, 0); for (int i = 0; i < n; ++i) { std::cin >> ws[i]; } std::sort(std::begin(ws), std::end(ws)); for (int i = 0; i < n; ++i) { cs[i + 1] = ws[i] + cs[i]; } int q; std::cin >> q; while (q--) { int t; std::cin >> t; if (t == 1) { ll s, k; std::cin >> s >> k; std::cout << answer(ws, cs, s, k) << std::endl; } else if (t == 2) { // naive version... ll w; std::cin >> w; auto hint = std::upper_bound(std::cbegin(ws), std::cend(ws), w); auto it = ws.insert(hint, w); ll i = std::distance(std::begin(ws), it); cs.insert(std::cbegin(cs) + i + 1, 0); cs[i + 1] = cs[i]; for (++i; i < cs.size(); ++i) { cs[i] += w; } } else if (t == 3) { // naive version... ll w; std::cin >> w; auto hint = std::prev(std::upper_bound(std::cbegin(ws), std::cend(ws), w)); auto it = ws.erase(hint); ll i = std::distance(std::begin(ws), it); cs.erase(std::cbegin(cs) + i + 1); for (++i; i < cs.size(); ++i) { cs[i] -= w; } } } return 0; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 | #include <iostream> #include <vector> #include <algorithm> using ll = long long; int answer(std::vector<ll> const &ws, std::vector<ll> const &cs, const ll s, const ll k) { int eaten = 0; ll weight = s; ll wdiff = k - weight; // stack keeps (max_pos (excluded), num_eaten) std::vector<std::pair<ll, ll>> stack = { {0, 0} }; while (wdiff > 0) { auto next_max = std::lower_bound(std::cbegin(ws), std::cend(ws), weight); if (next_max == std::begin(ws)) { // we can't eat any other fish return -1; } auto gain = std::prev(next_max); // how much we need to either achieve k or reach next MAX ll need = wdiff - 1; // let's hope this (-1) with not break everything if (next_max != std::cend(ws)) { need = std::min(*next_max - weight, need); } // let's eat this fish ll dist = std::distance(std::cbegin(ws), next_max); if (stack.back().first + 1 == dist) { // by eating this fish we will use whole range auto [pm, pv] = stack.back(); stack.back() = { dist, pv + 1 }; } else { stack.push_back({ dist, 1 }); } weight += *gain; wdiff -= *gain; need -= *gain; eaten += 1; // let's try achieve next MAX while (need >= 0 && stack.size() >= 2) { auto [cpos, cnum] = stack[stack.size() - 1]; auto [mpos, mnum] = stack[stack.size() - 2]; // optimization: use `cs` to check if we are going to eat whole range ll base = cs[cpos - 1]; auto lim = std::cbegin(cs) + cpos - cnum + 1; auto rng = std::upper_bound(std::cbegin(cs) + mpos + 1, lim, need, [=](auto &&v, auto &&t) { return -v <= -(base - t); }); ll range = std::distance(rng, lim); ll gained = base - *std::prev(rng); need -= gained; weight += gained; wdiff -= gained; eaten += range; if (rng == std::cbegin(cs) + mpos + 1) { // we need to eat whole range // merge both ranges stack.pop_back(); stack.pop_back(); stack.push_back({ cpos, mnum + cpos - mpos }); } else { // update max on stack (we have enough) stack.back().second += range; } } if (need >= 0 && wdiff > 0) { return -1; // we can't advance MAX } if (wdiff <= 0) { break; } } return eaten; } int main() { std::ios::sync_with_stdio(false); int n; std::cin >> n; std::vector<ll> ws(n); std::vector<ll> cs(n + 1, 0); for (int i = 0; i < n; ++i) { std::cin >> ws[i]; } std::sort(std::begin(ws), std::end(ws)); for (int i = 0; i < n; ++i) { cs[i + 1] = ws[i] + cs[i]; } int q; std::cin >> q; while (q--) { int t; std::cin >> t; if (t == 1) { ll s, k; std::cin >> s >> k; std::cout << answer(ws, cs, s, k) << std::endl; } else if (t == 2) { // naive version... ll w; std::cin >> w; auto hint = std::upper_bound(std::cbegin(ws), std::cend(ws), w); auto it = ws.insert(hint, w); ll i = std::distance(std::begin(ws), it); cs.insert(std::cbegin(cs) + i + 1, 0); cs[i + 1] = cs[i]; for (++i; i < cs.size(); ++i) { cs[i] += w; } } else if (t == 3) { // naive version... ll w; std::cin >> w; auto hint = std::prev(std::upper_bound(std::cbegin(ws), std::cend(ws), w)); auto it = ws.erase(hint); ll i = std::distance(std::begin(ws), it); cs.erase(std::cbegin(cs) + i + 1); for (++i; i < cs.size(); ++i) { cs[i] -= w; } } } return 0; } |