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Coding-Decoded/March2022/Java/ValidParentheses.java at master · Sunchit/Coding-Decoded · GitHub

25 lines (24 loc) · 685 Bytes

class Solution {

// TC O(len(s))

// SC O(len(s))

public boolean isValid(String s) {

Stack<Character> st =new Stack<Character>();

for(char c: s.toCharArray()){

if(st.empty()){

st.push(c);

} else{

char topChar = st.peek();

if(topChar == '(' && c ==')'){

st.pop();

} else if(topChar == '{' && c =='}'){

st.pop();

} else if(topChar == '[' && c ==']'){

st.pop();

} else{

st.push(c);

}

return st.empty();

}