zoukankan      html  css  js  c++  java
  • pat 1093. Count PAT's (25)

    1093. Count PAT's (25)

    时间限制
    120 ms
    内存限制
    65536 kB
    代码长度限制
    16000 B
    判题程序
    Standard
    作者
    CAO, Peng

    The string APPAPT contains two PAT's as substrings. The first one is formed by the 2nd, the 4th, and the 6th characters, and the second one is formed by the 3rd, the 4th, and the 6th characters.

    Now given any string, you are supposed to tell the number of PAT's contained in the string.

    Input Specification:

    Each input file contains one test case. For each case, there is only one line giving a string of no more than 105 characters containing only P, A, or T.

    Output Specification:

    For each test case, print in one line the number of PAT's contained in the string. Since the result may be a huge number, you only have to output the result moded by 1000000007.

    Sample Input:
    APPAPT
    
    Sample Output:
    2
    解:dp法,P[i]表示 到i位置前P的个数;PA[i]表示 到i位置前PA的个数;PAT[i]表示 到i位置前PAT的个数,状态转移条件代码里。

    代码:

    #include<iostream>
    #include<cstdlib>
    #include<cstdio>
    #include<cstring>
    using namespace std;
    int main()
    {
        string s;
        cin>>s;
        int len=s.length();
        int *P=new int[len+10];
        int *PA=new int[len+10];
        int *PAT=new int[len+10];
        memset(P,0,sizeof(P));
        memset(PA,0,sizeof(PA));
        memset(PAT,0,sizeof(PAT));
        for(int i=0;i<len;i++)
        {
            if(s[i]=='P')
            {
                if(i==0)
                    P[i]=1;
                else
                    P[i]=P[i-1]+1;
            }
            else
            {
               if(i==0) P[i]=0;
               else P[i]=P[i-1];
            }
        }
        for(int i=0;i<len;i++)
        {
            if(s[i]=='A'&&P[i]!=0)
            {
                if(i==0)
                    PA[i]=1;
                else
                {
                    PA[i]=PA[i-1]+P[i];
                    PA[i]%=1000000007;       
                }
            }
            else
            {
               if(i==0) PA[i]=0;
               else PA[i]=PA[i-1];
            }
        }
        for(int i=0;i<len;i++)
        {
            if(s[i]=='T'&&PA[i]!=0)
            {
                if(i==0)
                    PAT[i]=1;
                else
                 {
                    PAT[i]=PAT[i-1]+PA[i];
                    PAT[i]%=1000000007;   
                 }  
            }
            else
            {
               if(i==0) PAT[i]=0;
               else PAT[i]=PAT[i-1];
            }
        }
        cout<<PAT[len-1]<<endl;
    }
    

    版权声明:本文为博主原创文章,未经博主允许不得转载。

  • 相关阅读:
    C# SQL 语句 更新树表的全路径
    递归树 C#
    javascript 在没有找到何时的脚本管理框架前, 使用如下方式在页面上使用脚本
    JS keycode keydown keypress 事件
    C# asp.net 解压缩
    弹出新窗体出现的含有[object]空白页面问题的解决
    include define【11/12/15】
    HDOJ 2191 珍惜现在,感恩生活 【动态规划 多重背包】
    HDOJ 1114 Piggy-Bank 【动态规划 完全背包】
    HDOJ 2602 Bone Collector 【动态规划 01背包】
  • 原文地址:https://www.cnblogs.com/Tobyuyu/p/4965283.html
Copyright © 2011-2022 走看看