2021 RoboCom 世界机器人开发者大赛-高职组（复赛）解题报告 | 珂学家

前言

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题解

2021 RoboCom 世界机器人开发者大赛-高职组（复赛）解题报告。

模拟题为主，包含进制转换等等。

最后一题，是对向量/自定义类型，重定义小于操作符。

7-1 人工智能打招呼

分值: 15分

考察点: 分支判定，判重技巧

#include 

using namespace std;

int main() {
    int n;
    cin >> n;
    set<string> hp;
    for (int i = 0; i < n; i++) {
        string id; cin >> id;
        if (hp.find(id) == hp.end()) {
            cout << "Hello " << id << ", how are you?\n";
            hp.insert(id);
        } else {
            cout << "Hi " << id<< "! Glad to see you again!\n";
        }
    }

    return 0;
}

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7-2 人工智能数字翻译

分值: 20分
考察：进制转换，10和27进制互转

#include 

using namespace std;

int main() {
    string a;
    int d;
    cin >> a >> d;
    if (d == 10) {
        string res;
        int s = stoi(a);
        while (s > 0) {
            int r = s % 27;
            if (r >= 0 && r < 10) {
                res += (char)(r + '0');
            } else {
                res += (char)(r - 10 + 'A');
            }
            s /= 27;
        }
        if (res.empty()) res = "0";
        reverse(res.begin(), res.end());
        // 去掉前置多余的0
        if (res[0] == '0' && res.size() > 0) {
            int pos = res.size() - 1;
            for (int i = 0; i < res.size(); i++) {
                if (res[i] != '0') {
                    pos = i;
                    break;
                }
            }
            res = res.substr(pos);
        }
        cout << res << "\n";
    } else {
        int64_t res = 0;
        string s = a;
        for (char c: s) {
            if (c >= '0' && c <= '9') {
                res = res * 27 + (c - '0');
            } else {
                res = res * 27 + (c - 'A' + 10);
            }
        }
        cout << res << "\n";
    }
    return 0;
}

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7-3 机器人拼图

分值: 20分

模拟

#include 

using namespace std;

int main() {
    int n, m;
    cin >> n >> m;

    vector<vector<int>> mat(n, vector<int>(m, 0));
    for (int i = 0; i < n * m; i++) {
        string op; cin >> op;

        int x = 0, y = 0;
        for (char c: op) {
            if (c == '1') {
                y = min(y + 1, m - 1);
            } else if (c == '3') {
                y = max(y - 1, 0);
            } else if (c == '2') {
                x = min(x + 1, n - 1);
            } else if (c == '4') {
                x = max(x - 1, 0);
            } else {
                if (mat[x][y] == 0) {
                    mat[x][y] = i + 1;
                }
            }
        }
    }
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            cout << mat[i][j] << " \n"[j == m - 1];
        }
    }

    return 0;
}

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7-4 PAT基础级排名

分值： 20分

思路: 排序 + 分组循环

因为存在同分的情况，所以分组循环，是种优雅的写法

#include 

using namespace std;

struct Stu {
    string name;
    int score;
};

int main() {

    int n, L;
    cin >>n >> L;

    vector<Stu> arr;
    for (int i = 0; i < n; i++) {
        Stu stu;
        cin >> stu.name >> stu.score;
        arr.push_back(stu);
    }
    sort(arr.begin(), arr.end(), [](auto &a, auto &b) {
        if (a.score != b.score) return a.score > b.score;
        return a.name < b.name;
    });

    int levels[6] = {0, 30, 50, 60, 80, 100}; 
    auto resolve = [levels](int a) {
        for (int i = 5; i >= 0; i--) {
            if (a > levels[i]) return i + 1;
        }
        return 0;
    };
    int x = L + 1;
    int m = n;
    int acc = 0;
    int rank = 0;
    for (int i = 0;i < n; i++) {
        Stu &stu = arr[i];
        int level = resolve(stu.score);
        if (x > level) {
            m = m - acc;
            acc = 0;
            x = level;
            rank = 1;
        }
        acc++;
        if (acc > 1 && arr[i].score == arr[i - 1].score) {
            
        } else {
            rank = acc;
        }
        if (x != 0) {
            cout << stu.name << " " << x << " " 
                << stu.score << "/" << levels[x] << " "
                << rank << "/" << m << "\n";
          } else {
            cout << stu.name << "\n";
          }
    }
    
    return 0;
}

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7-5 人工智能刑警

分值： 25分

思路: 自定义类型重定义小于操作符

因为这边采用map(底层是树)，所以需要对自定义类型重定义小于操作符。

#include 

using namespace std;

struct T {
    vector<int> feature;
    bool operator<(const T&lhs) const {
        int n = feature.size();
        for (int i = 0; i < n; i++) {
            int v1 = feature[i], v2 = lhs.feature[i];
            if (v1 != v2) return v1 < v2;
        }
        return 0;
    }
};

int main() {
    map<T, string> hp;
    int n, f;
    cin >> n >> f;
    for (int i = 0; i < n; i++) {
        T t;
        for (int j = 0; j < f; j++) {
            int v; cin >> v;
            t.feature.push_back(v);
        }
        string name; cin >> name;
        hp[t] = name;
    }

    while (true) {
        bool ok = true;
        T t2;
        for (int i = 0; i < f; i++) {
            int v; 
            if (cin >> v && (v == 0 && i == 0)) {
                ok = false;
                break;
            }
            t2.feature.push_back(v);
        }
        if (!ok) break;
        
        if (hp.find(t2) != hp.end()) {
            cout << hp[t2] << "\n";
        } else {
            cout << "Pass"  << "\n";
        }
    }
    
    return 0;
}

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