Leetcode 402 Solution

This article provides solution to leetcode question 402 (remove-k-digits)

https://leetcode.com/problems/remove-k-digits

Solution

class Solution { public: string removeKdigits(string num, int k) { string res = "";
for (char ch : num) { while (k && res.size() && ch < res[res.size() - 1]) { res.pop_back(); k--; }
res.push_back(ch); }
if (k >= res.size()) return "0"; else res = res.substr(0, res.size() - k);
for (int i = 0; i < res.size(); i++) if (res[i] != '0') return res.substr(i);
return "0"; } };