homework_detail - 蒙青创OJ

#include <bits/stdc++.h>
using namespace std;
stack<int>stk, stkmin;
int main() {
	int n;
	cin >> n;
	for (int i = 1; i <= n; i++) {
		string s;
		cin >> s;
		if (s == "pop") {
			if (stk.empty()) {
				cout << "error" << endl;
			} else{
				if(stk.top()==stkmin.top()){
					stkmin.pop();
				}
				stk.pop();
			}
		} else if (s == "top") {
			if (stk.empty()) {
				cout << "error" << endl;
			} else
				cout << stk.top() << endl;
		} else if (s == "push") {
			int x;
			cin >> x;
			if (stk.empty()) {
				stk.push(x);
				stkmin.push(x);
			} else {
				stk.push(x);
				if (x <= stkmin.top())
					stkmin.push(x);
			}
		} else if (s == "get_min") {
			if(!stkmin.empty())
				cout << stkmin.top() << endl;
			else cout<<"error"<<endl;
		}
	}
	return 0;
}

#include <bits/stdc++.h>
using namespace std;
int main()
{
	string s;
	cin>>s;
	stack<char>stk;
	for(int i=0;s[i]!='@';i++){
		if(s[i]=='('){
			stk.push(s[i]);
		}
		if(s[i]==')'){
			if(stk.empty()){
				cout<<"NO"<<endl;
				return 0;
			}
			else stk.pop();
		}
	}
	if(stk.empty())
		cout<<"YES"<<endl;
	else cout<<"NO"<<endl;
	return 0;
}

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

int main() {
	cin >> T;
	while (T--) {
		string s;
		cin >> s;
		stack<char>stk;
		int flag = 0;
		for (int i = 0; i < s.size(); i++) {
			if (s[i] == '(' || s[i] == '[')
				stk.push(s[i]);
			else {
				if (s[i] == ')' && (stk.empty() || stk.top() != '(')) {
					cout << "No" << endl;
					flag = 1;
				} else if (s[i] == ']' && (stk.empty () || stk.top() != '[')) {
					cout << "No" << endl;
					flag = 1;
				}
				else if(s[i]==')' && stk.top()=='('){
					stk.pop();
				}
				else if(s[i]==']' && stk.top()=='['){
					stk.pop();
				}
			}
			if (flag == 1)
				break;
		}
		if (flag == 1)
			continue;
		else {
			if (!stk.empty()) {
				cout << "No" << endl;
			} else
				cout << "Yes" << endl;
		}
	}
	return 0;
}

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

int main() {
	string s;
	stack<char>stk;
	cin >> s;
	for (int i = 0; i < s.size(); i++) {
		if (s[i] == '@') {
			if(!stk.empty())stk.pop();
		} else
			stk.push(s[i]);
	}
	vector<char>v;
	while (!stk.empty()) {
		v.push_back(stk.top());
		stk.pop();
	}
	for (int i = v.size() - 1; i >= 0; i--) {
		cout << v[i];
	}
	return 0;
}

/*
in:1 2 3 4 5
out:5 3 2 4 1
out:4 3 2 1 5
*/
#include <bits/stdc++.h>
using namespace std;
const int N = 1005;
int n, m;
int in[N], out[N];

int main() {
	cin >> n >> m;
	for (int i = 1; i <= n; i++) {
		cin >> in[i];
	}
	while (m--) {
		for (int i = 1; i <= n; i++) {
			cin >> out[i];
		}
		int In = 1, Out = 1;
		stack<int>stk;
		while (In <= n) {
			//1.栈为空
			if (stk.empty()) {
				stk.push(in[In]);
				In++;
				continue;
			}
			//2.栈不为空 且栈顶和out[Out]不相同
			if (!stk.empty() && stk.top() != out[Out]) {
				stk.push(in[In]);
				In++;
			}
			//3.栈不为空，且栈顶和out[Out]相同
			if (!stk.empty() && stk.top() == out[Out]) {
				stk.pop();
				Out++;
			}
		}
		while (!stk.empty() && out[Out] == stk.top()) {
			stk.pop();
			Out++;
		}
		if (stk.empty() && Out == n + 1 && In == n + 1) {
			cout << "Yes" << endl;
		} else
			cout << "No" << endl;
	}
	return 0;
}

#include <bits/stdc++.h>
using namespace std;
stack<int>stk;
int n;

int main() {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		string s;
		cin >> s;
		if (s == "empty") {
			if (!stk.empty())
				cout << "no" << endl;
			else
				cout << "yes" << endl;
		} else if (s == "size") {
			cout << "size = " << stk.size() << endl;
		} else if (s == "top") {
			if (!stk.empty()) {
				cout << "top = " << stk.top() << endl;
			} else
				cout << "top fail" << endl;
		} else if (s == "pop") {
			if (!stk.empty()) {
				cout << "pop " << stk.top() << endl;;
				stk.pop();
			} else
				cout << "pop fail" << endl;
		} else {
			int x;
			cin >> x;
			stk.push(x);
		}
	}
	return 0;
}

#include <bits/stdc++.h>
using namespace std;
const int N = 3e6+5;
int n,a[N],f[N];
stack<int>stk;
int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>a[i];
	}
	for(int i=n;i>=1;i--){
		while(!stk.empty() && a[i]>=a[stk.top()])stk.pop();
		if(stk.empty())f[i] = 0;
		else f[i] = stk.top();
		stk.push(i);
	}
	for(int i=1;i<=n;i++){
		cout<<f[i]<<" ";
	}
	return 0;
}

#include <bits/stdc++.h>
using namespace std;
const int N = 3e6 + 5;
int n, a[N], f[N];
stack<int>stk;

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> a[i];
	}
	for (int i = n; i >= 1; i--) {
		while (!stk.empty() && a[i] > a[stk.top()])
			stk.pop();
		if (!stk.empty())
			f[i] = stk.top();
		else
			f[i] = n + 1;
		stk.push(i);
	}
	int res = 0;
	for (int i = 1; i <= n; i++) {
		res += f[i] - i - 1;
	}
	cout << res << endl;
	return 0;
}

#include <bits/stdc++.h>
using namespace std;
#define int long long
const int N = 3e6 + 5;
int n, a[N], f[N];
stack<int>stk;

signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> a[i];
	}
	int res = 0;
	for (int i = n; i >= 1; i--) {
		while (!stk.empty() && a[i] >= a[stk.top()]) {
			res += stk.top() - i + 1;
			stk.pop();
		}
		if (!stk.empty()) {
			res += stk.top() - i + 1;
		}
		stk.push(i);
	}
	cout << res << endl;
	return 0;
}

#include <bits/stdc++.h>
using namespace std;
const int N = 1e6 + 5;
#define int long long
int n;
int h[N], v[N], f[N];

signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> h[i] >> v[i];
	}
	//1.找左边比h[i]大的
	stack<int>stk;
	for (int i = 1; i <= n; i++) {
		while (!stk.empty() && h[i] >= h[stk.top()])
			stk.pop();
		if (!stk.empty())
			f[stk.top()] += v[i];
		stk.push(i);
	}
	while (!stk.empty())
		stk.pop();
	for (int i = n; i >= 1; i--) {
		while (!stk.empty() && h[i] >= h[stk.top()])
			stk.pop();
		if (!stk.empty())
			f[stk.top()] += v[i];
		stk.push(i);
	}
	int res = 0;
	for (int i = 1; i <= n; i++) {
		res = max(res, f[i]);
	}
	cout << res << endl;
	return 0;
}

#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 5;
int n, a[N];
int stk1[N], top1, stk2[N], top2;

int main() {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> a[i];
	}
	int res = 0;
	for (int i = 1; i <= n; i++) {
		//top1维护单调递增
		while (top1 && a[i] <= a[stk1[top1]])
			--top1;
		while (top2 && a[i] > a[stk2[top2]])
			--top2;
		//找stk1中比stk2[top2]大的数
		int id = upper_bound(stk1 + 1, stk1 + top1 + 1, stk2[top2]) - stk1;
		if (id <= top1)
			res = max(res, i - stk1[id] + 1);
		stk1[++top1] = i;
		stk2[++top2] = i;
	}
	cout << res << endl;
	return 0;
}

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Status: Live...
Problem: 12
Open Since: 2025-5-15 0:00
Deadline: 2025-5-22 23:59
Extension: 24 hour(s)

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