牛客网历年计算机考研复试上机题在线练习

成绩排序

#include <iostream>
#include <algorithm>
#include <string>
#include <cstdio>
using namespace std;
struct Node {
    string name;
    int score;
} node[500];
bool cmp(const Node& a, const Node& b) {
    return a.score < b.score;
}
bool cmp1(const Node& a, const Node& b) {
    return a.score > b.score;
}
int main() {
    int n, type;
    while (scanf("%d%d", &n, &type) == 2) {
        for (int i = 0; i < n; i++) {
            cin >> node[i].name >> node[i].score;
        }
        if (type == 1) {
            stable_sort(node, node+n, cmp);

        } else if(type == 0) {
            stable_sort(node, node+n, cmp1);
        }
        for (int i = 0; i < n; i++) {
                cout << node[i].name << " " <<  node[i].score << endl;
            }
    }
    return 0;
}

代理服务器

#include <iostream>
#include <cstring>
#include <cstdio>
using namespace std;
int solve(char p[][16], int n, char q[][16], int m) {
    int Max = -1;
    int i, j;
    for (i = 0; i < n; i++) {
        for (j = 0; j < m; j++) {
            if (!strcmp(p[i], q[j])) {
                Max = max(j, Max);
                break;
            }
        }
        if (j == m)
            return 0;
    }
    if (n == 1 && Max != -1)   // 只有一个代理服务器，还不能解决剩下的问题
        return -1;
    return 1 + solve(p, n, q+Max, m-Max);
}
int main() {
    int n, m;
    char p[1005][16];
    char q[5005][16];
    cin >> n;
    for (int i = 0; i < n; i++) {
        scanf("%s", p[i]);
    }
    cin >> m;
    for (int i = 0; i < m; i++) {
        scanf("%s", q[i]);
    }
    cout << solve(p, n, q, m) << endl;
    return 0;
}

手机键盘

#include <iostream>
#include <string>
using namespace std;
int pos[26][2] = {{1,1},{1,2},{1,3},{2,1},{2,2},{2,3},{3,1},{3,2},{3,3},
    {4,1},{4,2},{4,3},{5,1},{5,2},{5,3},{6,1},{6,2},{6,3},{6,4},
    {7,1},{7,2},{7,3},{8,1},{8,2},{8,3},{8,4}};    // 保存每个字母所在的键盘及其位置
int main() {
    string str = "";
    while (cin >> str) {
        int time = 0;
        for (int i = 0 ; i < str.length(); i++) {
            if (i == 0) {
                time += pos[str[0]-'a'][1];    // 第一个字母不需要等待，直接加按键时间
            } else {
                if (pos[str[i]-'a'][0] == pos[str[i-1]-'a'][0]) {
                    time += 2;    // 等待时间
                }
                time += pos[str[i]-'a'][1];
            }
        }
        cout << time << endl;
    }
    return 0;
}

球的半径和体积

#include <iostream>
#include <cstdio>
#include <cmath>
using namespace std;
const double PI = acos(-1);
int main() {
    int cx, cy, cz, px, py, pz;
    while (scanf("%d%d%d%d%d%d", &cx, &cy, &cz, &px, &py, &pz) == 6) {
        double radius = sqrt((px-cx)*(px-cx) + (py-cy)*(py-cy) + (pz-cz)*(pz-cz));
        double area = PI*radius*radius*radius*4/3;
        printf("%.3f %.3f\n", radius, area);
    }
    return 0;
}

成绩排序

#include <iostream>
#include <algorithm>
using namespace std;
struct Stu {
    int id;
    int score;
};
bool cmp(const Stu& a, const Stu& b) {
    if (a.score == b.score)
        return a.id < b.id;
    return a.score < b.score;
}
int main() {
    int n;
    Stu stu[105];
    while (cin >> n) {
        for (int i = 0; i < n; i++) {
            cin >> stu[i].id >> stu[i].score;
        }
        sort(stu, stu+n, cmp);
        for (int i = 0; i < n; i++) {
            cout << stu[i].id << " " << stu[i].score << endl;
        }
    }
    return 0;
}

二叉树遍历

#include <iostream>
using namespace std;
struct TreeNode {
    TreeNode* left;
    TreeNode* right;
    char val;
    TreeNode(char c) : val(c), left(NULL), right(NULL){}
};

TreeNode* createTree(string str, int & index) {   // 根据前序遍历建树
    TreeNode *r = NULL;
    if (index < str.length() && str[index] != '#') {
        r = new TreeNode(str[index]);
        r->left = createTree(str, ++index);
        r->right = createTree(str, ++index);
    }
    return r;
}
void InOrderTraverse(TreeNode* root) {
    if (root == NULL)
        return;
    InOrderTraverse(root->left);
    cout << root->val << " ";
    InOrderTraverse(root->right);
}
int main() {
    string str;
    while (cin >> str) {
        int index = 0;
        TreeNode* root = createTree(str, index);
        InOrderTraverse(root);
        cout << endl;
    }
    return 0;
}

玛雅人的密码

#include <iostream>
#include <map>
#include <queue>
#include <set>
using namespace std;
char aim[] = {'2', '0', '1', '2'};
typedef pair<string, int> _pair;
int n;
bool judge(string str) {
    int len = str.length();
    for (int i = 0; i < len; i++) {
        if (str[i] == '2' && str[i+1] == '0' && str[i+2] == '1' && str[i+3] == '2')
            return true;
    }
    return false;
}
int BFS(string str) {
    queue<_pair> q;
    set<string> s;
    q.push(make_pair(str, 0));

    while (!q.empty()) {
        _pair p = q.front();
        q.pop();
        string tmp = p.first;
        if (judge(tmp)) {
            return p.second;
        } else {
            for (int i = 0; i < n-1; i++) {
                swap(tmp[i], tmp[i+1]);
                if (!s.count(tmp))
                    q.push(make_pair(tmp, p.second+1));
                swap(tmp[i], tmp[i+1]);
            }
        }
    }
    return -1;
}

int main() {
    while (cin >> n) {
        string str;
        cin >> str;
        cout << BFS(str) << endl;
    }
    return 0;
}