Codeforces 1305B Kuroni and Simple Strings

题目链接

给你一个只包含'(',')'的串，匹配的串为可行串，问最少几次去掉几个可行串，能使得剩下的串无法再去掉其他串

贪心可解，双指针，最左的一定和最右的匹配，这样就能保证一次k=1，然后直接搜索匹配即可

#include<bits/stdc++.h>
using namespace std;
#define ms(x,y) memset(x, y, sizeof(x))
#define lowbit(x) ((x)&(-x))
typedef long long LL;
typedef pair<int,int> pii;

const int maxn = 1005;

char str[maxn];


void run_case() {
    cin >> (str+1);
    int r = strlen(str+1), l = 1;
    vector<int> a, b;
    while(l < r) {
        if(str[l] == ')') l++;
        else {
            if(str[r] == '(') r--;
            else {
                a.push_back(l), b.push_back(r);
                l++, r--;
            }
        }
    }
    if(a.size()) {
        cout << "1" << "
";
    } else {
        cout << "0
";
        return;
    }
    cout << a.size() * 2 << "
";
    for(auto i : a) cout << i << " ";
    for(auto i = b.rbegin(); i != b.rend(); ++i) cout << *i << " ";
}

int main() {
    ios::sync_with_stdio(false), cin.tie(0);
    cout.flags(ios::fixed);cout.precision(2);
    //int t; cin >> t;
    //while(t--)
    run_case();
    cout.flush();
    return 0;
}