1136 A Delayed Palindrome （20 分)

Consider a positive integer N written in standard notation with k+1 digits a​i​​ as a​k​​⋯a​1​​a​0​​ with 0 for all i and a​k​​>0. Then N is palindromic if and only if a​i​​=a​k−i​​ for all i. Zero is written 0 and is also palindromic by definition.

Non-palindromic numbers can be paired with palindromic ones via a series of operations. First, the non-palindromic number is reversed and the result is added to the original number. If the result is not a palindromic number, this is repeated until it gives a palindromic number. Such number is called a delayed palindrome. (Quoted from https://en.wikipedia.org/wiki/Palindromic_number )

Given any positive integer, you are supposed to find its paired palindromic number.

Input Specification:

Each input file contains one test case which gives a positive integer no more than 1000 digits.

Output Specification:

For each test case, print line by line the process of finding the palindromic number. The format of each line is the following:

A + B = C

where A is the original number, B is the reversed A, and C is their sum. A starts being the input number, and this process ends until C becomes a palindromic number -- in this case we print in the last line C is a palindromic number.; or if a palindromic number cannot be found in 10 iterations, print Not found in 10 iterations. instead.

Sample Input 1:

97152

Sample Output 1:

97152 + 25179 = 122331
122331 + 133221 = 255552
255552 is a palindromic number.

Sample Input 2:

196

Sample Output 2:

196 + 691 = 887
887 + 788 = 1675
1675 + 5761 = 7436
7436 + 6347 = 13783
13783 + 38731 = 52514
52514 + 41525 = 94039
94039 + 93049 = 187088
187088 + 880781 = 1067869
1067869 + 9687601 = 10755470
10755470 + 07455701 = 18211171
Not found in 10 iterations.

分析：大数模拟，最后一个测试点应该是大数边界，因为数可能是1000位的，所以如果用int 和long long 都会超出范围。

#include<cstdio>
#include<cstring>
#include<iostream>
#include<cmath>
#include<algorithm>
#include<string>
#include<unordered_set>
#include<map>
#include<vector>
#include<set>
using namespace std;
string rev(string s){
    reverse(s.begin(),s.end());
    return s;
}

string add(string s1,string s2){
    ;
    string s=s1;
    ;i>=;i--){
        '+carry;
        s[i]=temp%+';
        carry=temp/;
    }
    ) s='+s;
    return s;
}

bool ispali(string s){
    int len=s.length();
    ;i<len;i++){
        ]){
            return false;
        }
    }
    return true;
}

int main(){
#ifdef ONLINE_JUDGE
#else
    freopen("1.txt", "r", stdin);
#endif
    string num,s;
    cin>>num;
    if(num==rev(num)){
        cout<<num<<" is a palindromic number.";
        ;
    }
    ;
    bool flag=false;
    while(k--){
        s=rev(num);
        string sum=add(s,num);
        flag=ispali(sum);
        cout<<num<<" + "<<s<<" = "<<sum<<endl;
        if(flag==true){
            cout<<sum<<" is a palindromic number.";
            break;
        }
        num=sum;
    }
    ){
        cout<<"Not found in 10 iterations.";
    }

    ;
}