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LearnStack & Monotonic Stack

Min Stack (Design)

Read the lesson → understand the pattern → then code. Tutor works offline (built-in teacher); optional Cursor/Gemini keys upgrade chat quality.

Topic refresher: Stack — Last In, First Out

LIFO for matching, undo, and next-greater patterns.

stack<char> st;
for (char c : s) {
    if (/* open */) st.push(c);
    else {
        if (st.empty() || st.top() != need) return false;
        st.pop();
    }
}
return st.empty();
Stack & Monotonic Stack

Min Stack (Design)

Medium
LeetCode
2/3
MediumStack & Monotonic StackLeetCode #155

Min Stack

Support push/pop/top/getMin in O(1). Keep a parallel min stack.

Examples

Example 1

Input

push -2
push 0
push -3
getMin
pop
top
getMin

Output

-3
0
-2

Stuck? Take a nudge

C++17