题解 | 配置文件恢复

#include <iostream>
#include <vector>
#include <sstream>
using namespace std;

bool is_matched(string s, string t) {
    for(int i = 0; i < t.size(); ++i) {
        if(s[i] != t[i]) return false;
    }
    return true;
}

int main() {
    vector<string> ans;
    string command;
    while(getline(cin, command)) {
        stringstream ss(command);
        string token;
        vector<string> commands;
        while(getline(ss, token, ' ')) {
            commands.push_back(token);
        }
        if(commands.size() > 2) {
            ans.push_back("unknown command");
        }
        else if(commands.size() == 2) {
            if(is_matched("reset", commands[0]) && is_matched("board", commands[1])) {
                if(is_matched("reboot", commands[0]) && is_matched("backplane", commands[1])) {
                    ans.push_back("unknown command");
                } else {
                    ans.push_back("board fault");
                }
                
            }
            else if(is_matched("board", commands[0])) {
                if(is_matched("add", commands[1])) {
                    if(is_matched("backplane", commands[0]) && is_matched("abort", commands[1])) ans.push_back("unknown command");
                    else ans.push_back("where to add");
                }
                else if(is_matched("delete", commands[1])) ans.push_back("no board at all");
                else ans.push_back("unknown command");
            }
            else if(is_matched("reboot", commands[0]) && is_matched("backplane", commands[1])) {
                ans.push_back("impossible");
            }
            else if(is_matched("backplane", commands[0]) && is_matched("abort", commands[1])) {
                ans.push_back("install first");
            } else ans.push_back("unknown command");
        } else if(commands.size() == 1) {
            if(is_matched("reset", commands[0])) ans.push_back("reset what");
            else ans.push_back("unknown command");
        } else ans.push_back("unknown command");
    }
    
    for(const string& s: ans) {
        cout << s << endl;
    }
    return 0;
}