奇怪，把RE的数据自己下下来测明明没有RE，还很快

#include<iostream>
#include<cstdio>
#include<string>
#include<algorithm>
#include<sstream>
using namespace std;
string month[12]={"01","02","03","04","05","06","07","08","09","10","11","12"};
string day[12]={"31","28","31","30","31","30","31","31","30","31","30","31"};
string day2[12]={"31","29","31","30","31","30","31","31","30","31","30","31"};
int to_num(string s)
{
    stringstream ss(s);
    int n;
    ss>>n;
    return n;
}
string to_string(int n)
{
    string s;
    stringstream ss;
    ss<<n;
    s=ss.str();
    return s;
}
int main()
{
    int cnt=0;
    string s;
    cin>>s;
    string t;
    cin>>t;
    string s2=s.substr(0,4);
    string t2=t.substr(0,4);
    int nums=to_num(s2);
    int numt=to_num(t2);
    for(int i=nums;i<=numt;i++)
    {
        string a=to_string(i);
        string b=to_string(i);
        reverse(b.begin(),b.end());
        string k="";
        k+=a;
        k+=b;
        bool type1=0;
        bool type2=0;
        int f;
        string b1="";
        b1+=b[0];
        b1+=b[1];
        string b2="";
        b2+=b[2];
        b2+=b[3];
        for(int j=0;j<12;j++)
        {
            if(b1==month[j])
            {
                type1=1;
                f=j;
                break;
            }
        }
        if(to_num(b2)<=to_num(day[f]) && to_num(a)%4!=0)type2=1;
        if(to_num(b2)<=to_num(day2[f]) && to_num(a)%4==0)type2=1;
        if(k>=s && k<=t && type1==1 && type2==1)
        {
            //cout<<k<<endl;
            cnt++;
        }
    }
    cout<<cnt;
    return 0;
}

以上是代码（那两个函数是用来在字符串和数字之间变化的）