USACO题解源代码

package Karl.Water;

/*
LANG: JAVA
TASK: beads
*/


import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.PrintWriter;
import java.util.LinkedList;

public class beads {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		try {
			BufferedReader br = new BufferedReader(new FileReader("beads.in"));
			PrintWriter pw = new PrintWriter (new FileWriter("beads.out"));
			
			int length = Integer.parseInt(br.readLine());
			String temp = br.readLine();
			LinkedList<Character> necklace = new LinkedList<Character>();
			for (int i=0;i<length;i++) {
				necklace.add(temp.charAt(i));
			}
			
			int max = 0;
			for (int i=0;i<length;i++) {
				char remove = necklace.removeFirst();
				char first = necklace.getFirst();
				int position = 0;
				necklace.addLast(remove);
				
				int result = 0;
				boolean allW = false;
				if (necklace.getFirst()=='w'){
					int end1 = find(necklace,0,length,0); 
					result = end1 + 1;
					if (end1<necklace.size()-1){
						int end2 = find (necklace,end1+1,length,0);
						first = necklace.get(end2);
						position = end2;
						result = result + end2 - end1;
					}else {
						allW = true;
					}
				} else {
					int end = find(necklace,0,length,0);
					position = end ;
					result = result + end + 1;
				}
				if (!allW){
					if (necklace.getLast()=='w') {
						int end1 = find(necklace, length-1,position,1);
						int end2 = find(necklace,end1-1,position,1);
						
						if (necklace.get(end2)==first){
							result = result ;
						}else {
							result = result + length - end1;
							result = result + end1 - end2 ;
						}
					}else {
						if (necklace.getLast()==first){
							result = result; 
						}else {
							int end = find(necklace,length-1,position,1);
							result = result + length - end ;	
						}
					}
				}
				if (result >=max){
					max = result;
				}
			}
			pw.println(max);
			pw.close();
			br.close();
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	public static int find(LinkedList<Character> necklace,int startPoint ,int endPoint,int direction){
		if (direction ==0 ){
			int i=startPoint+1;
			for (;i<=endPoint-1;i++){
				if (necklace.get(i)!=necklace.get(startPoint)&&necklace.get(i)!='w'){
					break;
				}
			}
			return i-1;
		} else {
			int i=startPoint-1;
			for (;i>=endPoint+1;i--){
				if (necklace.get(i)!=necklace.get(startPoint)&&necklace.get(i)!='w'){
					break;
				}
			}
			return i+1;
		}
	}

}

（2）

package Karl.Water;

/*
LANG: JAVA
TASK: friday
*/

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;

public class friday {
	public static void main(String[] args) throws IOException {
		int mon=0;
		int tue=0;
		int win=0;
		int thur=0;
		int fri=0;
		int sat=0;
		int sun=0;
		int j=0;
		int [][]days = {{31,28,31,30,31,30,31,31,30,31,30,31},{31,29,31,30,31,30,31,31,30,31,30,31}};
		BufferedReader br = new BufferedReader(new FileReader("friday.in"));
		PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("friday.out")));
		int N = Integer.parseInt(br.readLine());
		int flag;
		for(int year = 1900;year<=1900+N-1;year++){
			flag =(year%4==0 && year%100!=0) || year%400 == 0 ? 1 : 0;
			for(int k=0;k<12;k++){
				for(int i=0;i<days[flag][k];i++,j++){
					if(i==12){
						if(j%7==0){
							mon++;
						}else if(j%7==1){
							tue++;
						}else if(j%7==2){
							win++;
						}else if(j%7==3){
							thur++;
						}else if(j%7==4){
							fri++;
						}else if(j%7==5){
							sat++;
						}else if(j%7==6){
							sun++;
						}
					}
				}
			}
		}
		out.println(sat+" "+sun+" "+mon+" "+tue+" "+win+" "+thur+" "+fri);
		out.close();
		System.exit(0);
	}
}

（3）

package Karl.Water;

/*
LANG: JAVA
TASK: gift1
*/

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.StringTokenizer;

public class gift1 {
	
	public static void main(String[] args) throws NumberFormatException, IOException {
		HashMap<String,Integer> hash = new HashMap<String,Integer>();
		StringTokenizer str;
		BufferedReader br = new BufferedReader(new FileReader("gift1.in"));
		PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("gift1.out")));
		int memnum = Integer.parseInt(br.readLine());
		String[] s = new String[memnum];
		for(int i=0;i<memnum;i++){
			s[i] = br.readLine();
			hash.put(s[i], 0);
		}
		for(int i=0;i<memnum;i++){
			String name = br.readLine();
			for(int j=0;j<memnum;j++){
				if(s[j].equals(name)){
					str=new StringTokenizer(br.readLine());
					int m = Integer.parseInt(str.nextToken());
					int n = Integer.parseInt(str.nextToken());
					if(n==0){}else{
					hash.put(s[j], hash.get(s[j])-m+m%n);}
					for(int k=0;k<n;k++){
						String na = br.readLine();
						hash.put(na,hash.get(na)+ m/n);
					}
				}
			}
		}
		for(int i=0;i<memnum;i++){
			out.println(s[i]+" "+hash.get(s[i]));
		}
		out.close();
		System.exit(0);
	}
	
}

（4）

package Karl.Water;

/*
LANG: JAVA
TASK: milk2
*/

import java.util.*;
import java.io.*;
public class milk2 {
	boolean time[]=new boolean[1000007];
	int n,a,b,max_use,max_rex,tmp1,tmp2,start=10000007,stop=0;
	public static void main(String[] args) throws IOException 
	{
		new milk2().run();
	}
	void run() throws IOException
	{
		Scanner cin=new Scanner(new FileReader("milk2.in"));
		PrintWriter cout=new PrintWriter(new BufferedWriter(new FileWriter("milk2.out")));
		n=cin.nextInt();
		for(int i=1;i<=n;i++)
		{
			a=cin.nextInt();
			b=cin.nextInt();
			start=start<a ? start:a;
			stop=stop>b ? stop:b;
			for(int j=a;j<b;j++)
				time[j]=true;
		}
		for(int i=start;i<=stop;i++)
		{
			if(time[i])
				tmp1++;
			else
			{
				max_use=max_use>tmp1 ? max_use:tmp1;
				tmp1=0;
			}
			if(!time[i])
			{
				tmp2++;
			}
			else
			{
				max_rex=max_rex>tmp2 ? max_rex:tmp2;
				tmp2=0;
			}
		}
//		System.out.println(max_use+" "+max_rex);
		cout.println(max_use+" "+max_rex);
		cout.close();
		System.exit(0);
	}
}

（5）、

这个程序有点问题，到第六七组数据时就出错了，

某君如果知道怎么写留个言也行。

package Karl.Water;

/*
LANG: JAVA
TASK: transform
*/

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;

public class transform {
	public static void Reflection(char[][] a,int n){
		char k;
		int i,j;
		for(j=0;j<n;j++){
			for(i=0;i<n/2;i++){
				k = a[j][i];
				a[j][i] = a[j][n-1-i];
				a[j][n-1-i] = k;
			}
		}
	}
	public static void rotate(char a[][],int N)
	{
	    int layer;
	    for(layer=0; layer<N/2; layer++)
	    {
	        int first = layer;              
	        int last = N-1-layer;               
	        int i;
	        for(i=layer; i<last; i++)
	        {
	                int offset = i-layer;
	                char top = a[first][i];
	                a[first][i] = a[last-offset][first];
	                a[last-offset][first] = a[last][last-offset];
	                a[last][last-offset] = a[i][last];
	                a[i][last] = top;
	        }
	    }
	}
	public static boolean judge(char[][] a,char[][] b,int n){
		for(int i=0;i<n;i++){
			for(int j=0;j<n;j++){
				if(a[i][j]!=b[i][j]){
					return false;
				}
			}
		}
		return true;
	}

	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader br = new BufferedReader(new FileReader("transform.in"));
		PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("transform.out")));
		char[][] a = new char[1000][1000];
		char[][] b = new char[1000][1000];
		char[][] c = new char[1000][1000];
		int n = Integer.parseInt(br.readLine());
		String s = new String();
		int i,j,k=0;
		for(i=0;i<n;i++){
			s = br.readLine();
			for(j=0;j<n;j++){
				a[i][j] = s.charAt(j);
				c[i][j] = s.charAt(j);
			}
		}
		for(i=0;i<n;i++){
			s = br.readLine();
			for(j=0;j<n;j++){
				b[i][j] = s.charAt(j);
			}
		}
		for(int p=0;p<4;p++){
			transform.rotate(a, n);
			if(transform.judge(a, b, n)){
				k++;
				if(p==3) out.println(6);
				else{
					out.println(p+1);
					break;
				}
			}
		}
		if(k<1){
			transform.Reflection(a, n);
			if(transform.judge(a, b, n)){
				k++;
				out.println(4);
			}
		}
		if(k!=1&&k!=2){
			for(int p=0;p<3;p++){
				transform.rotate(a, n);
				if(transform.judge(a, b, n)){
					k++;
					out.println(5);
				}
			}
		}
		if(k==0){
			out.println(7);
		}
		out.close();
		System.exit(0);
	}
}