USACO Section 1.1 Broken Necklace

最新推荐文章于 2023-12-02 22:53:12 发布

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最新推荐文章于 2023-12-02 22:53:12 发布

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CC 4.0 BY-SA版权

文章标签： c/c++

原文链接：http://www.cnblogs.com/yangce/archive/2011/10/27/2225994.html

本文提供了一个模拟算法题的实现思路及C++代码示例，并附带了多个测试数据集供验证算法正确性和性能。

花大力气写的模拟。。。等搜索练好了再回来做，另外把测试数据发一下。。

/*
  ID:linyvxi1
  PROG:beads
  LANG:C++
*/
#include <stdio.h>
#include <string.h>
int main()
{
	FILE*	fin=fopen("beads.in","r");
	FILE*	fout=fopen("beads.out","w");

	int n;
	char str[400];
	fscanf(fin,"%d",&n);
	fscanf(fin,"%s",str);
	bool flag1=false,flag2=false;
	int i=0,j=strlen(str)-1;
	char stat=str[0];
	//while(i<=j&&(str[i]==str[i+1]||str[i+1]=='w'||str[i]=='w'))
	while(i<=j&&(str[i]==stat||str[i]=='w'))
		i++;
	stat=str[strlen(str)-1];
//	while(j>=0&&(str[j]==str[j+1]||str[j]=='w'||str[j+1]=='w'))
	while(j>=0&&(str[j]==stat||str[j]=='w'))
		j--;
	int max,temp=0;
	if(i>=j){
		fprintf(fout,"%d\n",strlen(str));
		return 0;
	}//如果全相同。。。
	else	max=i+strlen(str)-1-j;
	for(i=1;i<=strlen(str)-1;i++){
		int n=i,m=i-1,k;
		k=i-1;
		while(str[k]=='w')
			k++;
		stat=str[k];
//		stat=str[i-1];
		while(m>=0&&(str[m]==stat||str[m]=='w'))//标志位
			m--;//左边是i-1-m个
		k=n;
		while(str[k]=='w')
			k++;
		stat=str[k];
		while(n<=strlen(str)-1&&(str[n]==stat||str[n]=='w'))
			n++;//右边是n-i个
		if(m!=-1&&n!=strlen(str)){//如果都没数到头
			int num=i-1-m+n-i;
			if(num>max)
				max=num;
		}
//		stat=str[i-1];
		else if(m==-1&&n!=strlen(str)){//如果左边到头了右边没到头
			k=i-1;
			while(str[k]=='w')
				k++;
			stat=str[k];
			if(str[strlen(str)-1]==stat||str[strlen(str)-1]=='w'){//如果左边还能继续往下走
				m=strlen(str)-1;
				while(str[m]==stat||str[m]=='w')
					m--;//右边是n-i个
				//int sum=n-i+1+i-0+1+strlen(str)-1-m+1;
				int sum=n-i+strlen(str)-1-m+i;
				if(sum>max)
					max=sum;
			}
			else {
				int sum=i+n-i;
				if(sum>max)
					max=sum;
			}
		}
//		stat=str[i];
		else if(m!=-1&&strlen(str)==n){//如果左边没到头右边到头了
			k=i;
			while(str[k]=='w')
				k++;
			stat=str[k];
			if(str[0]=='w'||str[0]==stat){//如果右边还能继续走下去
				n=0;
				while(str[n]==stat||str[n]=='w')
					n++;//又走了n个
//				int sum=n-0+1+i-1-m+1+strlen(str)-1-i+1;
				int sum=n+i-1-m+strlen(str)-1-i+1;
				if(sum>max)
					max=sum;
			}
			else{
//				int sum=i-1-m+1+strlen(str)-1-i+1;
				int sum=i-1-m+strlen(str)-i;
				if(sum>max)
					max=sum;
			}
		}
		else{//两边都到头了
			max=strlen(str);
			break;
		}
	}
	fprintf(fout,"%d\n",max);
}

Here are the test data inputs:

------- test 1 ----
29
wwwbbrwrbrbrrbrbrwrwwrbwrwrrb
------- test 2 ----
3
rrr
------- test 3 ----
77
rwrwrwrwrwrwrwrwrwrwrwrwbwrwbwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwr
------- test 4 ----
17
wwwwwwwwwwwwwwwww
------- test 5 ----
50
bbrrrbrrrrrrrrbrbbbrbrrbrrrrbbbrbrbbbbbrbrrrbbrbbb
------- test 6 ----
8
rrwwwwbb
------- test 7 ----
200
rrrrrrrrrrrrrrrrrrrrbbbbbbbbbbbbbbbbbbbbrrrrrrrrrrrrrrrrrrrrbbbbbbbbbbbbbbbbbbbbrrrrrrrrrrrrrrrrrrrrbbbbbbbbbbbbbbbbbbbbrrrrrrrrrrrrrrrrrrrrbbbbbbbbbbbbbbbbbbbbrrrrrrrrrrrrrrrrrrrrbbbbbbbbbbbbbbbbbbbb
------- test 8 ----
350
rrbbrbbbwbwwbwbbbbwwrrbbwbrwbrwbbbrbrwrwbrwwwrrbbrrwrbbrwbwrwwwrbrwwwwwrwbwwwrrbrrbbbrbrbbbrbbbrbbwbbbbbrbrrbrwwbrrrrwbwrwrbbwbwrbrbrwwbrrbwbrwwbwwwbrbwrwbwbrbbbwrbwwrrrbwbwbbbbbrrwwwrbrwwrbbwrbbrbbrbwrrwwbrrrbrwbrwwrbwbwrrrbwrwrrbrbbwrwrbrwwwrwbwrrwwwwrrrwrrwbbwrwwrwrbwwbwrrrrbbwrbbrbwwwwwbrbbrbbrbrwbbwbwwbbbbbwwwrbwwbbbwrwwbbrrwrwbwrrwwwrrrwrrwww
------- test 9 ----
333
rwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwb

转载于:https://www.cnblogs.com/yangce/archive/2011/10/27/2225994.html