BestCoder Round #89

题目链接：​​点击打开链接​​

Fxx and string

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 131072/65536 K (Java/Others)

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Total Submission(s): 97    Accepted Submission(s): 47

Problem Description

Young theoretical computer scientist Fxx get a string which contains lowercase letters only.

The string S contains n lowercase letters S1S2…Sn.Now Fxx wants to know how many three tuple (i,j,k) there are which can meet the following conditions:

1、 i,j,k are adjacent into a geometric sequence.

2、 Si=' y' ,Sj=' r' ,Sk=' x'.

3.Either j|i or j|k

 

Input

T(1≤T≤100) indicating the number of test cases.

T lines follow, each line contains a string, which contains only lowercase letters.(The length of string will not exceed 10000).

 

Output

For each case, output the answer.

 

Sample Input

2 xyyrxx yyrrxxxxx

 

Sample Output

0 2

 

Source

​​BestCoder Round #89 ​​

问题描述

青年理论计算机科学家Fxx得到了一个只包含小写字母的字符串。

字符串的长度为\:nn，下标从1开始，第\:i\:i位的字母为\:s_isi，现在Fxx想知道有多少三元组\:(i,j,k)\:(i,j,k)满足下列条件

1、i,j,k\:i,j,k三个数成等比数列

2、s_i=si='yy',s_j=,sj='rr',s_k=,sk='xx'

3.i/ji/j和k/jk/j中必须有整数

输入描述

第一行一个整数\:T(1\leq T\leq100)\:T(1≤T≤100)表示数据组数。

接下来\:T\:T行，每行一个仅包含小写字母的字符串（字符串长度不超过\:1000010000）

输出描述

输出共\:T\:T行。

每行一个整数表示答案。

输入样例

2 xyyrxx yyrrxxxxx

输出样例

0 2

思路：刚开始只考虑了公比大于 1 的情况，唉

#include<cstdio>
#include<algorithm>
#include<cstring>
using namespace std;
char str[10010];
int main()
{
  int t;
  scanf("%d",&t);
  while(t--)
  {
    scanf("%s",str+1);
    int len=strlen(str+1);
    int ans=0; 
    for(int i=1;i*4<=len;i++)
    {
      if(str[i]=='y')
      {
        int cnt=2;
        while(i*cnt*cnt<=len)
        {
          if(str[i*cnt]=='r'&&str[i*cnt*cnt]=='x')
            ans++;
          cnt++;
        }
      }
      if(str[i]=='x')
      {
        int cnt=2;
        while(i*cnt*cnt<=len)
        {
          if(str[i*cnt]=='r'&&str[i*cnt*cnt]=='y')
            ans++;
          cnt++;
        }
      }
    }
    printf("%d\n",ans);
  }
  return 0;
}