UVa 1597-Searching the Web

这个题比较长，如果按照题目要求一步一步做的话。也不是很难。但是如果想提高代码精简度和可读性高效性确实不容易，想轻松AC还是用C++，C语言的输入输出。Java很容易超时。普通算法要10s左右。

Java代码 ：

import java.util.*;

public class Main1597 {

	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		int t = scan.nextInt();
		String s = scan.nextLine();
		String[][] str = new String[105][1500]; 
		int[] row = new int[t];
		Arrays.fill(row, 0);
		for(int i=0; i<t; i++) {
			while(true) {
				str[i][row[i]] = scan.nextLine();
				if(str[i][row[i]].equals("**********")) {
					break;
				}
				row[i] ++;
			}
		}
		int n = scan.nextInt();
		String ss = scan.nextLine();
		for(int j=0; j<n; j++) {
			String line = scan.nextLine();
			String[][] ans = new String[t][1000];
			int[] cnt = new int[1000];
			Arrays.fill(cnt, 0);
			if(line.contains(" AND ")) {
				int end = 0;
				while(line.charAt(end)!=' ')end ++;
				String A = line.substring(0, end);
				String B = line.substring(end+5, line.length());
				for(int i=0; i<t; i++) {
					int a = 0, b = 0;
					for(int r=0; r<row[i]; r++) {
						if(str[i][r].toLowerCase().contains(A)) {
							a = 1;
						}
						if(str[i][r].toLowerCase().contains(B)) {
							b = 1;
						}
					}
					if(a==1 && b==1) {
						for(int r=0; r<row[i]; r++) {
							if(str[i][r].toLowerCase().contains(A) || str[i][r].toLowerCase().contains(B)) {
								ans[i][cnt[i]++] = str[i][r];
							}
						}
					}
				}
			}else if(line.contains(" OR ")) {
				int end = 0;
				while(line.charAt(end)!=' ')end ++;
				String A = line.substring(0, end);
				String B = line.substring(end+4, line.length());
				for(int i=0; i<t; i++) {
					for(int r=0; r<row[i]; r++) {
						if(str[i][r].toLowerCase().contains(A) || str[i][r].toLowerCase().contains(B)) {
							ans[i][cnt[i]++] = str[i][r];
						}
					}
				}
			}else if(line.contains("NOT ")) {
				int end = 0;
				while(line.charAt(end)!=' ')end ++;
				//String A = line.substring(0, end);
				String B = line.substring(4, line.length());
				for(int i=0; i<t; i++) {
					int con = 0;
					for(int r=0; r<row[i]; r++) {
						if(!str[i][r].toLowerCase().contains(B)) {
							//ans[i][cnt[i]++] = str[i][r];
							con ++;
						}
					}
					if(con == row[i]) {
						for(int r=0; r<row[i]; r++) {
							ans[i][cnt[i]++] = str[i][r];
						}
					}
				}
			}else {
				for(int i=0; i<t; i++) {
					for(int r=0; r<row[i]; r++) {
						if(str[i][r].toLowerCase().contains(line)) {
							ans[i][cnt[i]++] = str[i][r];
						}
					}
				}
			}
			int flag = 0, m = 0;
			for(int k=0; k<t; k++) {
				if(m > 0 && cnt[k] != 0)
					System.out.println("----------");
				for(int l=0; l<cnt[k]; l++) {
						//System.out.println("----------");
					    System.out.println(ans[k][l]);
					    flag = 1;
					    m ++;
				}
			}
			if(flag == 0)
				System.out.println("Sorry, I found nothing.");
			System.out.println("==========");
		}
	}
}

来自互联网的C++代码 ：

//{头文件模板
#include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>
using namespace std;
//}头文件模板
#define rep(i,b) for(int i=0; i<(b); i++)
#define foreach(i,a) for(__typeof((a).begin()) i=a.begin(); i!=(a).end(); ++i)
#define FOR for (int j = limit[i]; j < limit[i + 1]; j++)
typedef bool Bit[1505];

int n, lines, m;          // n文档数, lines行数, m请求数
int limit[105];           // limit[i]: 第i篇文档从第几行开始

string doc[1505];         // 存储内容
map<string, Bit> Index;   // Index[单词]: B标记了哪些行出现过

// 用s来更新Index
void upDate(string s, int p) {
    string word;
    foreach(it, s) {
        if (isalpha(*it)) *it = tolower(*it); // 变小写
        else *it = ' '; // 非字母变空白
    }

    stringstream ss(s);
    while (ss >> word) Index[word][p] = true;
}

int main() {
    //{section: 文档数据输入
    scanf("%d ", &n);
    rep(i, n) {
        limit[i] = lines;
        while (getline(cin, doc[lines]), doc[lines] != "**********") {
            upDate(doc[lines], lines);
            lines++;
        }
    }
    limit[n] = lines;//}

    //{section: 对获取的请求输出对应的内容
    string  s;                      // s存储每次得到的请求
    Bit     mark;                   //{记录哪些行应该输出
                                    //}mark的解释: 因为每篇文档要用10个'-'隔开,比较麻烦,最后统一处理
    bool    *A, *B;

    scanf("%d ", &m);
    for (int iii = 0; iii < m; iii++) {
        getline(cin, s);

        //{subsection: 计算出mark中介
        if (s[0] == 'N') {
            A = Index[s.substr(4)];
            rep(i, n) {
                bool logo = true;
                FOR if (A[j]) { logo = false; break; }
                FOR mark[j] = logo;
            }
        } else if (s.find("AND") != string::npos) {
            int p = s.find(" AND ");
            A = Index[s.substr(0, p)];
            B = Index[s.substr(p + 5)];
            memset(mark, 0, sizeof(mark));
            bool hasA, hasB;    // 在同一文章中, 两个词是否都出现
            rep(i ,n) {
                hasA = hasB = false;    // 默认没出现
                FOR if (A[j]) { hasA = true; break; }
                FOR if (B[j]) { hasB = true; break; }
                if (!(hasA&&hasB)) continue;
                FOR mark[j] = (A[j] || B[j]);
            }
        } else if (s.find("OR") != string::npos) {
            int p = s.find(" OR ");
            A = Index[s.substr(0, p)];
            B = Index[s.substr(p + 4)];
            rep(i, lines) mark[i] = (A[i] || B[i]);
        } else memcpy(mark, Index[s], sizeof(mark));//}

        //{subsection: 输出mark
        bool hasOut = false, needOut = false;    // 记录上一轮是否有输出文档
        rep(i, n) {
            if (hasOut) needOut = true;
            hasOut = false;
            FOR if (mark[j]) {
                if (needOut) {
                    cout << "----------\n";
                    needOut = false;
                }
                cout << doc[j] << "\n";
                hasOut = true;
            }
        }
        if (!(needOut||hasOut)) cout << "Sorry, I found nothing.\n";
        cout << "==========\n";//}
    }//}

    return 0;
}