UKEUKEUKE

真的是*了dog了，提交四五次UKE，点还不一样，输入输出修改了还不行。
代码：

#include <bits/stdc++.h>

using namespace std;

char str[110];
bool matched[110];

int main(void) {
    // scanf("%s", str);
    cin >> str;
    int n = strlen(str);

    for (int i = 0; i < n; ++i) {
        char now = str[i];

        if (now == '(' || now == '[') {
            continue;
        }

        char need, bad;
        if (now == ')') {
            need = '(';
            bad = '[';
        } else {
            need = '[';
            bad = '(';
        }

        for (int j = i - 1; j >= 0; --j) {
            if (!matched[j] && str[j] == bad) {
                break;
            }
            if (!matched[j] && str[j] == need) {
                matched[j] = 1;
                matched[i] = 1;
                break;
            }
        }
    }

    for (int i = 0; i < n; ++i) {
        char now = str[i];

        if (matched[i]) {
            putchar(now);
        } else {
            if (now == '(' || now == ')') {
                // putchar('(');
                // putchar(')');
                cout << "()";
            } else {
                // putchar('[');
                // putchar(']');
                cout << "[]";
            }
        }
    }
    // putchar('\n');
    cout << endl;

    return 0;
}

提交记录：
https://www.luogu.com.cn/record/39255855
https://www.luogu.com.cn/record/39255830
https://www.luogu.com.cn/record/39255786
https://www.luogu.com.cn/record/39255536 https://www.luogu.com.cn/record/39255153