亲测AC
```cpp
#include<bits/stdc++.h>
using namespace std;
bitset<100000001>z;
int zs[5000000],a,b,y,o,u;
int zx,zd;
int find(int l,int r,int k){
int m;
while(l+1<r){
m=(l+r)/2;
if(zs[m]<=k)l=m;
else r=m;
}
if(k-zs[l]<=zs[r]-k)return l;
else return r;
}
void write(int x){
if(x>9)write(x/10);
putchar(x%10+'0');
return;
}
int read(){
int x=0;char c=getchar();
while(c<'0'||c>'9')c=getchar();
while(c>='0'&&c<='9')x=(x<<1)+(x<<3)+(c^48),c=getchar();
return x;
}
int main(){
a=read(),b=read();
zs[1]=2,y=1;
for(int i(3);i<=b;i+=2){
if(z[i]==1)continue;
y++,zs[y]=i,o=i<<1;
for(int j(i+o);j<=b;j+=o)z[j]=1;
}
zx=find(1,y,a);zd=find(1,y,b);
for(int i(zx);i<=zd;i++){
o=zs[i],u=0;
while(o>0){
u*=10;
u+=o%10;
o/=10;
}
if(zs[i]==u)write(zs[i]),printf("\n");
}
return 0;
}
by HEROBRINEH @ 2024-03-05 18:16:03
@[HEROBRINEH](/user/1113507)
源代码上有什么建议吗
by Zzz123456789101112 @ 2024-03-05 18:28:30