程序员面试题精选100题(46)－对称子字符串的最大长度
题目：输入一个字符串，输出该字符串中对称的子字符串的最大长度。比如输入字符串“google”，由于该字符串里最长的对称子字符串是“goog”，因此输出4。
思路，把每个都看成是对称中心，然后向外扩展。。
int GetLongestSymmetricalLength_2(char* pString){ if(pString == NULL) return 0; int symmeticalLength = 1; char* pChar = pString; while(*pChar != '\0') { // Substrings with odd lengt char* pFirst = pChar - 1; char* pLast = pChar + 1; while(pFirst >= pString && *pLast != '\0' && *pFirst == *pLast) { pFirst--; pLast++; } int newLength = pLast - pFirst - 1; if(newLength > symmeticalLength) symmeticalLength = newLength; // Substrings with even length pFirst = pChar; pLast = pChar + 1; while(pFirst >= pString && *pLast != '\0' && *pFirst == *pLast) { pFirst--; pLast++; } newLength = pLast - pFirst - 1; if(newLength > symmeticalLength) symmeticalLength = newLength; pChar++; } return symmeticalLength;}