sorry,刚才打的有问题，现在再发一遍```cpp
#include <bits/stdc++.h>
using namespace std;
bool judge_prime(int a)
{
for(int i=2;i<=sqrt(a);i++)
if(a%i==0)
return false;
return true;
}
int num(int n)
{
int ws=0;
while(n!=0)
{ws++;n/=10;}
return ws;
}
int main()
{
int m,n;
cin>>m>>n;
vector <int> prm;
for(int i=m;i<=n;i++)
if(judge_prime(i))
prm.push_back(i);
for(int i=0;i<prm.size();i++)
{
if(num(prm[i])==1)
cout<<prm[i]<<endl;
else if(prm[i]==11)
cout<<11<<endl;
else if(num(prm[i])==3)
if(prm[i]/100==prm[i]%10)
cout<<prm[i]<<endl;
else if(prm[i]==1111)
cout<<1111<<endl;
else if(num(prm[i])==5)
if(prm[i]/10000==prm[i]%10
&&prm[i]/1000%10==prm[i]/10%10)
cout<<prm[i]<<endl;
else
if(prm[i]/1000000==prm[i]%10
&&prm[i]/100000%10==prm[i]/10%10
&&prm[i]/10000%10==prm[i]/100%10)
cout<<prm[i]<<endl;
}
return 0;
}
```
by wzy20110830 @ 2024-02-18 22:53:55
```cpp
#include <bits/stdc++.h>
using namespace std;
bool judge_prime(int a) {
for (int i = 2; i <= sqrt(a); i++) if (a % i == 0) return false;
return true;
}
int num(int n) {
int ws = 0;
while (n != 0) {
ws++;
n /= 10;
} return ws;
}
int main() {
int m, n;
cin >> m >> n;
vector <int> prm;
for (int i = m; i <= n; i++) if (judge_prime(i)) prm.push_back(i);
for (int i = 0; i < prm.size(); i++) {
if (num(prm[i]) == 1) cout << prm[i] << endl;
else if (prm[i] == 11) cout << 11 << endl;
else if (num(prm[i]) == 3) if (prm[i] / 100 == prm[i] % 10) cout << prm[i] << endl;
else if (prm[i] == 1111) cout << 1111 << endl;
else if (num(prm[i]) == 5) if (prm[i] / 10000 == prm[i] % 10 && prm[i] / 1000 % 10 == prm[i] / 10 % 10) cout << prm[i] << endl;
else if (prm[i] / 1000000 == prm[i] % 10 && prm[i] / 100000 % 10 == prm[i] / 10 % 10 && prm[i] / 10000 % 10 == prm[i] / 100 % 10) cout << prm[i] << endl;
} return 0;
}
```
by __er @ 2024-02-18 23:02:54