2017.9.9网易校招笔试最后一道编程解答

解答代码：

#include<iostream>#include<string>#include<algorithm>#include<vector>using namespace std;//判断是否是合法括号匹配序列bool panding(string ss, int n) {    int count = 0;    for (int i = 0; i<n; i++) {        if (ss[i] == '(') {            count++;        }        else if (ss[i] == ')') {            count--;        }        if (count<0)            return false;    }    if (count == 0)        return true;    else        return false;}//计算两个串的最长公共字串长度int lcs_len(string s1, string s2) {    int len1 = s1.size(), len2 = s2.size();    if (len1 == 0 || len2 == 0)return 0;    //定义二维数组dp[i][j]  代表串1从0~i这段与串2从0~j这段的公共子串的最大值    //赋初值dp[0~len1][0]=0   dp[0][0~len2]=0    vector<vector<int>> dp(len1 + 1, vector<int>(len2 + 1, 0));    for (int i = 1; i <= len1; i++) {        for (int j = 1; j <= len2; j++) {            if (s1[i - 1] == s2[j - 1]) {                //若相等则上层值+1                dp[i][j] = dp[i - 1][j - 1] + 1;            }            else {                //若不相等则等于交错值中的最大值                dp[i][j] = max(dp[i - 1][j], dp[i][j - 1]);            }        }    }    return dp[len1][len2];}int main(){    string s;    while (cin >> s)    {        string s2(s);        int shuzu[20] = { 0 };        int k = 0;        sort(s.begin(), s.end());        int i = 0;        do {            int lth =s.length();            if (panding(s, lth))            {                shuzu[i]=lcs_len(s, s2);                i++;                k++;            }        } while (next_permutation(s.begin(), s.end()));//找出s的所有排列        sort(shuzu, shuzu + 20);        int temp=0;        for (int t = 0; t < 20; t++)        {            if (shuzu[t] == shuzu[18])            {                temp++;            }        }        cout << temp << endl;    }    system("pause");    return 0;}