求助。java解算法题优化，总是超时

[椰子是只猫]

题目是不难。但是时间要求比较苛刻，总是超时。
无论是一维数组、二位数组储存，都试过了。也用list存储试过。都是部分测试数据超时。
本人小白一个，关于算法优化方面是一窍不通。请大家帮忙想一下。
本人写的部分代码如下：

一维数组：

import java.util.Scanner;
public class Main {

	public static void main(String[] args) {
		Scanner sc = new  Scanner(System.in);
		int a = sc.nextInt();
		
		String str1[] = new String[a];	//准考证
		String str2[] = new String[a];	//试机座位
		String str3[] = new String[a];	//考场
		
		for (int i=0;i<a;i++) {
			str1[i] = sc.next();
			str2[i] = sc.next();
			str3[i] = sc.next();
		}
		
		int n = sc.nextInt();
		int arr[] = new int[n];
		for (int i=0;i<n;i++) {
			arr[i] = sc.nextInt();
		}
		
		//查找
		for (int i=0;i<n;i++) {
			for (int j=0;j<a;j++) {
				if (arr[i]==Integer.parseInt(str2[j])) {
					System.out.println(str1[j] +" "+str3[j]);
				}
			}
		}
	}
}

通过list除去已选出的数据

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class Main {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		Scanner sc = new  Scanner(System.in);
		int a = sc.nextInt();
		
		String str1[] = new String[a];	//准考证
		String str2[] = new String[a];	//试机座位
		String str3[] = new String[a];	//考场
		List array = new ArrayList();
		
		for (int i=0;i<a;i++) {
			str1[i] = sc.next();
			str2[i] = sc.next();
			str3[i] = sc.next();
			array.add(str2[i]);
		}
		
		int n = sc.nextInt();
		int arr[] = new int[n];
		for (int i=0;i<n;i++) {
			arr[i] = sc.nextInt();
		}
		
		//查找
		for (int i=0;i<n;i++) {
//			for (ListIterator iter = array.listIterator();iter.hasNext();) {
			for (int j=0;j<array.size();j++) {
				if (arr[i]==Integer.parseInt((String) array.get(j))) {
					System.out.println(str1[j] +" "+str3[j]);
					array.remove(j);
				}
			}
		}
	}
}

[ITjavaman]

想请问下你是怎么测试内存和运行时间的

[ITjavaman]

找到了题目来源和评测方法，修改了下

public class Main {
	 public static void main(String[] args) {
		 Scanner sc = new  Scanner(System.in);
	        int a = sc.nextInt();
	         
	        Map<String, String> map = new HashMap<>();
	        StringBuffer sb = null;
	        String s = new String();
	        for (int i=0;i<a;i++) {
	        	sb = new StringBuffer();
	            sb.append(sc.next());
	            s = sc.next();
	            sb.append(" ");
	            sb.append(sc.next());
	            map.put(s, sb.toString());
	        }
	         
	        int n = sc.nextInt();
	        String arr[] = new String[n];
	        for (int i=0;i<n;i++) {
	            arr[i] = sc.next();
	        }

	        for (int i=0;i<n;i++) {
	             System.out.println(map.get(arr[i]));
	        }
	    }
}

[椰子是只猫]

这是个比赛的练习系统的题。。。。。从练习系统上测得。。。

[椰子是只猫]

引用 2 楼 ITjavaman 的回复:

找到了题目来源和评测方法，修改了下

public class Main {
	 public static void main(String[] args) {
		 Scanner sc = new  Scanner(System.in);
	        int a = sc.nextInt();
	         
	        Map<String, String> map = new HashMap<>();
	        StringBuffer sb = null;
	        String s = new String();
	        for (int i=0;i<a;i++) {
	        	sb = new StringBuffer();
	            sb.append(sc.next());
	            s = sc.next();
	            sb.append(" ");
	            sb.append(sc.next());
	            map.put(s, sb.toString());
	        }
	         
	        int n = sc.nextInt();
	        String arr[] = new String[n];
	        for (int i=0;i<n;i++) {
	            arr[i] = sc.next();
	        }

	        for (int i=0;i<n;i++) {
	             System.out.println(map.get(arr[i]));
	        }
	    }
}

测试了一下。。。还是超时

[galiniur0u]

楼主可以试试

public class Position {
	public static void main(String[] args){
		 Scanner sc = new  Scanner(System.in);
        int a = sc.nextInt();
         
        String str1[] = new String[a];    //准考证
        int str2[] = new int[a];    //试机座位
        String str3[] = new String[a];    //考场
         
        for (int i=0;i<a;i++) {
        	String zhun = sc.next();
        	int ji = sc.nextInt();
        	String kao = sc.next();
            str1[ji] = zhun;
            str2[ji] = ji;
            str3[ji] = kao;
        }
         
        int n = sc.nextInt();
        System.out.println(str1[n] + " " + str3[n]);
	}
}

[galiniur0u]

忘了加循环输入了

public class Position {
	public static void main(String[] args){
		 Scanner sc = new  Scanner(System.in);
        int a = sc.nextInt();
         
        String str1[] = new String[a];    //准考证
        int str2[] = new int[a];    //试机座位
        String str3[] = new String[a];    //考场
         
        for (int i=0;i<a;i++) {
        	String zhun = sc.next();
        	int ji = sc.nextInt();
        	String kao = sc.next();
            str1[ji] = zhun;
            str2[ji] = ji;
            str3[ji] = kao;
        }
         
        int n = sc.nextInt();
        for (int i=0;i<n;i++) {
        	int ji = sc.nextInt();
        	System.out.println(str1[ji] + " " + str3[ji]);
        }
	}
}

[ITjavaman]