PAT1024

题目链接：http://pat.zju.edu.cn/contests/pat-a-practise/1024
注意一点，必须要用字符串，long long 也会溢出！
 1 #include<iostream>
 2 #include<vector>
 3 #include<algorithm>
 4 #include<string>
 5 using namespace std;
 6 
 7 bool palindromic(string n)
 8 {
 9     string n1(n);
10     reverse(n.begin(), n.end());
11     if(n1 == n)
12         return true;
13     else
14         return false;
15 }
16 
17 string process(string n)
18 {
19     string n1(n);
20     reverse(n.begin(), n.end());
21     int carry(0);
22     string outcome;
23     for(int i=n1.size()-1; i>=0; --i)
24     {
25         int k=(n[i]-'0')+(n1[i]-'0')+carry;
26         carry=0;
27         if(k >= 10)
28             {carry = 1; k-=10;}
29         outcome.push_back((char)(k+'0'));
30     }
31     if(carry == 1)
32         outcome.push_back('1');
33     reverse(outcome.begin(), outcome.end());
34     return outcome;
35 }
36 
37 int main()
38 {
39     string n;
40     int k;
41     while(cin>>n>>k)
42     {
43         int m(0);
44         while(m <= k)
45             if(palindromic(n))
46             {
47                 cout<<n<<endl<<m<<endl;
48                 break;
49             }
50             else if(m == k)
51             {
52                 cout<<n<<endl<<m<<endl;
53                 break;
54             }
55             else
56             {
57                 n=process(n);
58                 ++m;
59             }
60     }
61     return 0;
62 }