2013
12-12

# Palindromes

A regular palindrome is a string of numbers or letters that is the same forward as backward. For example, the string "ABCDEDCBA" is a palindrome because it is the same when the string is read from left to right as when the string is read from right to left.

Now give you a string S, you should count how many palindromes in any consecutive substring of S.

There are several test cases in the input. Each case contains a non-empty string which has no more than 5000 characters.

Proceed to the end of file.

A single line with the number of palindrome substrings for each case.

aba
aa

4
3

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
#define MAXN 5005
char str[MAXN];

int main(){
while(~scanf("%s",&str)){
int len=strlen(str),l,r;
int ans=len;
for(int i=0;i<len;i++){
l=i-1,r=i+1;//奇数长度
while(l>=0&&r<len&&str[l]==str[r]){
l--,r++;
ans++;
}
l=i,r=i+1;//偶数长度
while(l>=0&&r<len&&str[l]==str[r]){
l--,r++;
ans++;
}
}
printf("%d\n",ans);
}
return 0;
}

1. 其实国内大部分公司对算法都不够重视。特别是中小型公司老板根本都不懂技术，也不懂什么是算法，从而也不要求程序员懂什么算法，做程序从来不考虑性能问题，只要页面能显示出来就是好程序，这是国内的现状，很无奈。

2. Gucci New Fall Arrivals

This is really nice to know. I hope it will be successful in the future. Good job on this and keep up the good work.

3. 第23行：
hash = -1是否应该改成hash[s ] = -1

因为是要把从字符串s的start位到当前位在hash中重置

修改提交后能accept，但是不修改居然也能accept