[day_050422] statistical palindrome

Statistical palindrome

Title source

Cattle from ： Statistical palindrome

Title Description

“ Palindrome string ” It's a string that is read both forward and backward , such as “level” perhaps “noon” And so on are palindrome strings . Hua Hua likes this palindrome string with symmetrical beauty very much , On her birthday, she got two gifts, one was string A And string B. Now she is very curious about whether there is any way to put the string B Insert string A Make the resulting string a palindrome string . You accept Huahua's request , Help her find out how many ways to insert a new string into a palindrome string . If the string B If the insertion position is different, it will be considered as different methods .
for example ：
A = “aba”,B = “b”. Here you are 4 Plant a handle B Insert A The way to ：

• stay A Before the first letter of : “baba” Not a palindrome
• In the first letter ‘a’ after : “abba” It's palindrome.
• In the letters ‘b’ after : “abba” It's palindrome.
• In the second letter ’a’ after “abab” Not a palindrome
  So the answer is 2

Input description

Each group has two lines of input data . The first line is string A The second behavior string B String length is less than 100 And contain only lowercase letters

Output description

Output a number , Represents a string B Insert string A Then the number of methods to form a palindrome string

Example 1

Input

aba
b

Output

2

Thought analysis

• How to judge palindrome string , Whether the inverted string is equal to the original string
• Traverse the first string , Insert the second string , Judge whether it is a palindrome string , Insert after the last position
• Define a... Every time you insert string Object to save the inserted results , Avoid modifying the original string

Code display

#include<iostream>
#include<algorithm>
#include<string>
using namespace std;

// Judging palindrome string 
bool IsPalindrome(string s)
{
    
    string temp = s;
    reverse(s.begin(), s.end());
    if (s == temp)
    {
    
        return true;
    }
    return false;
}

int main()
{
    
    string s1, s2;
    while (cin >> s1 >> s2)
    {
    
        int count = 0;
        // The back of the last position should also be spliced , So the circulation condition has "="
        for (int i = 0; i <= s1.size(); i++)
        {
    
            string s_temp = s1;
            s_temp.insert(i, s2);
            // Judge whether the spliced string is palindrome 
            if (IsPalindrome(s_temp))
            {
    
                count++;
            }
        }
        cout << count;
    }
    return 0;
}

summary

• call reverse(str.begin( ),str.end ( ) ), To a string Object is inverted
• str1.insert(pos ,str2 ), take str2 String insertion str1 Of pos Location
• Compare whether the strings are equal reference ：C/C++ Method of comparing strings in