回文字符串 参考代码

#include <bits/stdc++.h>
using namespace std;

typedef long long LL;
const int maxn = 1000000 + 100;
int T, n, l, r;
bool flag;
char str[maxn];

bool equalLqb(char ch) {
    return ch == 'l' || ch == 'q' || ch == 'b';
}

int main() {
#ifdef ExRoc
    freopen("test.txt", "r", stdin);
#endif
    ios::sync_with_stdio(false);

    scanf("%d", &T);
    while (T--) {
        scanf("%s", str + 1);
        n = strlen(str + 1);
        l = 0;
        for (int i = 1; i <= n; ++i) {
            if (!equalLqb(str[i])) {
                l = i;
                break;
            }
        }
        r = n + 1;
        for (int i = n; i >= 1; --i) {
            if (!equalLqb(str[i])) {
                r = i;
                break;
            }
        }
        if (l == 0) {
            printf("Yes\n");
            continue;
        }
        if ((r - l + 1) % 2 == 1) {
            l = r = (l + r) / 2;
        } else {
            l = (l + r) / 2;
            r = l + 1;
        }
        flag = true;
        for (; l >= 1 && r <= n; --l, ++r) {
            if (str[l] != str[r]) {
                flag = false;
                break;
            }
        }
        if (!flag || l != 0) {
            printf("No\n");
        } else {
            printf("Yes\n");
        }
    }

    return 0;
}