Submission #704115

# Submission time Handle Problem Language Result Execution time Memory
704115 2023-03-01T15:38:35 Z Cyanmond Land of the Rainbow Gold (APIO17_rainbow) C++17
12 / 100
588 ms 49588 KB
#include "rainbow.h"
#include <bits/stdc++.h>

void iterate(std::pair<int, int> &x, char c) {
    if (c == 'N') {
        --x.first;
    }
    if (c == 'S') {
        ++x.first;
    }
    if (c == 'E') {
        ++x.second;
    }
    if (c == 'W') {
        --x.second;
    }
}

struct UnionFind {
    int n;
    std::vector<int> data;
    int components;

    UnionFind(int n_) : n(n_), data(n, -1), components(n) {}

    int find(int v) {
        if (data[v] < 0) {
            return v;
        } else {
            return data[v] = find(data[v]);
        }
    }

    void merge(int a, int b) {
        a = find(a);
        b = find(b);
        if (a == b) {
            return;
        }
        if (data[a] > data[b]) {
            std::swap(a, b);
        }
        data[a] += data[b];
        data[b] = a;
        --components;
    }

    int countGroups() {
        return components;
    }
};

int R, C, sR, sC, M;
int msR;
std::string S;
int T;
std::map<std::pair<int, int>, bool> dataMap;
std::vector<std::pair<int, int>> points;
std::array<std::vector<std::pair<int, int>>, 2> landRanges;
std::vector<std::pair<int, int>> vxRanges;

void init(int r, int c, int sr, int sc, int m, char *s) {
    --sr, --sc;
    R = r;
    C = c;
    sR = sr;
    sC = sc;
    msR = sr;
    M = m;
    S.resize(M);
    for (int i = 0; i < M; ++i) {
        S[i] = s[i];
    }

    // check...
    if (R == 2) {
        T = 2;
    } else if (R <= 50 and C <= 50) {
        T = 1;
    } else {
        T = 3;
    }

    auto add = [&](const std::pair<int, int> &v, bool type) {
        if (type) {
            dataMap[v] = true;
        } else {
            if (dataMap.find(v) == dataMap.end()) {
                dataMap[v] = false;
            }
        }
    };
    std::pair<int, int> p = {sR, sC};
    if (T == 2) {
        add(p, true);
        for (int i = 0; i < M; ++i) {
            iterate(p, S[i]);
            add(p, true);
        };
        for (int x = 0; x < 2; ++x) {
            int l = 0;
            for (int i = 0; i < C; ++i) {
                if (dataMap[{x, i}]) {
                    if (l != i) {
                        landRanges[x].push_back({l, i - l});
                    }
                    l = i + 1;
                }
            }
            if (l != C) {
                landRanges[x].push_back({l, C - l});
            }
        }
        int l = 0;
        for (int i = 0; i < C; ++i) {
            if (dataMap[{0, i}] and dataMap[{1, i}]) {
                if (l != i) {
                    vxRanges.push_back({l, i - l});
                }
                l = i + 1;
            }
        }
        if (l != C) {
            vxRanges.push_back({l, C - l});
        }
    } else {
        auto addBlock = [&](const std::pair<int, int> &v) {
            add(v, true);
            for (int ax = -1; ax <= 1; ++ax) {
                for (int ay = -1; ay <= 1; ++ay) {
                    if (ax != 0 and ay != 0) {
                        continue;
                    }
                    if (ax == 0 and ay == 0) {
                        continue;
                    }
                    if (v.first + ax < 0 or v.first + ax >= R or v.second + ay < 0 or v.second + ay >= C) {
                        continue;
                    }
                    add({v.first + ax, v.second + ay}, false);
                }
            }
        };
        addBlock(p);
        for (int i = 0; i < M; ++i) {
            iterate(p, S[i]);
            addBlock(p);
        }
    }
}

int colour(int ar, int ac, int br, int bc) {
    --ar, --ac;
    if (T == 2) {
        const auto &ranges = (br - ar != 2 ? landRanges[ar] : vxRanges);
        auto itr = std::lower_bound(ranges.begin(), ranges.end(), std::make_pair(ac, 0));
        if (itr != ranges.begin()) {
            --itr;
            if (itr->first + itr->second <= ac) {
                ++itr;
            }
        }
        auto itr2 = std::lower_bound(ranges.begin(), ranges.end(), std::make_pair(bc, 0));
        return itr2 - itr;
    } else {
        auto add = [&](const std::pair<int, int> &v, bool type) {
            if (type) {
                dataMap[v] = true;
            } else {
                if (dataMap.find(v) == dataMap.end()) {
                    dataMap[v] = false;
                }
            }
        };
        for (int i = ac; i <= bc; ++i) {
            add({ar, i}, false);
            add({br - 1, i}, false);
            add({msR, i}, false);
        }
        for (int i = ar; i <= br; ++i) {
            add({i, ac}, false);
            add({i, bc - 1}, false);
        }
        std::vector<std::pair<int, int>> ids;
        int id = 0;
        int countRiver = 0;
        for (const auto &[pos, type] : dataMap) {
            const auto &[x, y] = pos;
            if (ar <= x and x < br and ac <= y and y < bc) {
                ids.push_back(pos);
                if (type) {
                    ++countRiver;
                }
            }
        }
        std::sort(ids.begin(), ids.end());
        ids.erase(std::unique(ids.begin(), ids.end()), ids.end());
        auto getid = [&](const std::pair<int, int> &p) {
            auto itr = std::lower_bound(ids.begin(), ids.end(), p);
            if (*itr != p) {
                return -1;
            }
            return (int)(itr - ids.begin());
        };
        UnionFind uft(ids.size());
        for (int i = 0; i < (int)ids.size(); ++i) {
            const auto &p = ids[i];
            if (dataMap[p]) {
                continue;
            }
            const auto &[x, y] = p;
            for (int ax = -1; ax <= 1; ++ax) {
                for (int ay = -1; ay <= 1; ++ay) {
                    if (ax != 0 and ay != 0) {
                        continue;
                    }
                    if (ax == 0 and ay == 0) {
                        continue;
                    }
                    const int nx = x + ax, ny = y + ay;
                    if (not(ar <= nx and nx < br and ac <= ny and ny < bc)) {
                        continue;
                    }
                    const int nid = getid({nx, ny});
                    if (nid == -1) {
                        continue;
                    }
                    if (not dataMap[{nx, ny}]) {
                        uft.merge(i, nid);
                    }
                }
            }
        }

        return uft.countGroups() - countRiver;
    }
}

Compilation message

rainbow.cpp: In function 'int colour(int, int, int, int)':
rainbow.cpp:185:13: warning: unused variable 'id' [-Wunused-variable]
  185 |         int id = 0;
      |             ^~
# Verdict Execution time Memory Grader output
1 Correct 28 ms 468 KB Output is correct
2 Incorrect 154 ms 544 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 172 ms 26152 KB Output is correct
4 Correct 179 ms 26244 KB Output is correct
5 Correct 181 ms 26476 KB Output is correct
6 Correct 195 ms 26556 KB Output is correct
7 Correct 210 ms 26804 KB Output is correct
8 Correct 181 ms 26224 KB Output is correct
9 Correct 178 ms 26220 KB Output is correct
10 Correct 175 ms 26472 KB Output is correct
11 Correct 199 ms 26492 KB Output is correct
12 Correct 177 ms 26112 KB Output is correct
13 Correct 167 ms 26224 KB Output is correct
14 Correct 184 ms 26548 KB Output is correct
15 Correct 197 ms 26460 KB Output is correct
16 Correct 173 ms 26164 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 588 ms 43220 KB Output is correct
3 Correct 489 ms 49588 KB Output is correct
4 Incorrect 375 ms 30272 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 28 ms 468 KB Output is correct
2 Incorrect 154 ms 544 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 28 ms 468 KB Output is correct
2 Incorrect 154 ms 544 KB Output isn't correct
3 Halted 0 ms 0 KB -