五位以内的对称素数

好久不做这种签到题，突然发现写了小bug的能力简直突飞猛进Orz，

#include
#include 
#include
using namespace std;
typedef long long ll;
int prime[100005];
int visit[100005];
int cnt = 0;
void init_prime() {

    memset(visit,0,sizeof(visit));
    for (int i = 2; i < 100005; i++) {
        if (visit[i] != 1) {
            prime[cnt++] = i;
            for (int j = i+i; j < 100005; j += i) {
                visit[j] = 1;
            }
        }
    }
}

bool is_prime(int a) {
    for (int i = 2; i <= a / 2; i++) {
        if (a % i == 0)
            return false;
    }
    return true;
}

bool judge_pa(const string &tmp) {
    int right = tmp.length() - 1;
    if (right == 0)
        return true;
    for (int i = 0; i <= tmp.length() / 2; i++) {
        if (tmp[i] != tmp[right])
            return false;
        right--;
    }
    return true;
}

int transfer2int(const string &tmp) {
    int ans = 0, k = 1;
    for (int i = tmp.length() - 1; i >= 0; i--) {
        ans += (tmp[i] - '0') * k;
        k *= 10;
    }
    return ans;
}

int main() {
    string str_list[5];
    init_prime();
    //for (int i=0;i>str_list[0]) {
        for (int i = 1; i < 5; i++) {
            cin >> str_list[i];
        }
        for(int i = 0; i < 5; i++) {
            if (str_list[i].length() > 5)
                puts("No");
            else {
                if (judge_pa(str_list[i]) && visit[transfer2int(str_list[i])] == 0)
                    puts("Yes");
                else
                    puts("No");
            }

        }
    }
    return 0;
}

涨姿势，单字符也算回文串，wa了好半天