ADD: More leetcode problems

Author: InclinedScorpio

Leetcode75/Intervals/minimum_number_of_arrays_to_burst_ballons.cpp

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+// https://leetcode.com/problems/minimum-number-of-arrows-to-burst-balloons/description/
+
+/**
+ * Logic: It's a interval question
+ * After sorting using the end point...
+ * .. we need to start picking each intervals from the first and not end
+ * ... as picking from first and comparing will give us result in minimum arrows
+ * 
+*/
+class Solution {
+public:
+    int findMinArrowShots(vector<vector<int>>& points) {
+        sort(points.begin(), points.end(), [](const vector<int>& x, const vector<int>& y){
+                return y[1]>x[1];
+        });
+
+        int result=0;
+        for(int i=0;i<points.size();) {
+            int currInd=i+1;
+            result++;
+            while(currInd<points.size() && points[currInd][0]<=points[i][1]) {
+                currInd++;
+            }
+            i=currInd;
+        }
+        return result;
+    }
+};

XDaysChallenge/90DaysChallenge/Day11/revision/next_warmer_temperature.cpp

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+// https://leetcode.com/problems/daily-temperatures
+
+/**
+ * Undestand pattern - find next >  so monotonic stack
+ * what to keep in .second -> index so can relate and give answer
+*/
+class Solution {
+public:
+    stack<pair<int, int>> store;
+
+    int getDayDiff(int item, int ind) {
+        pair<int, int> newItem = {item, ind};
+        int toReturn = 0;
+        while(!store.empty() && store.top().first<=item) {
+            store.pop();
+        }
+        int diff=0;
+        if(!store.empty())
+            diff = store.top().second - ind;
+        store.push(newItem);
+        return diff;
+    }
+
+    vector<int> dailyTemperatures(vector<int>& temperatures) {
+        vector<int> result;
+        for(int i=temperatures.size()-1;i>=0;i--)
+            result.push_back(getDayDiff(temperatures[i], i));
+        reverse(result.begin(), result.end());
+        return result;        
+    }
+};

XDaysChallenge/90DaysChallenge/Day11/revision/online_stock_span.cpp

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+// https://leetcode.com/problems/online-stock-span
+
+/**
+ * Pattern - find continuous last n item small or equal - monotonic stack
+ * understanding what to keep in .second here....
+*/
+class StockSpanner {
+public:
+
+    stack<pair<int, int>> store;
+
+    StockSpanner() {
+    }
+
+    int restructureStore() {
+        pair<int,int> topItem = store.top();
+        store.pop();
+        while(!store.empty() && store.top().first<=topItem.first) {
+            pair<int, int> restTopItem = store.top();
+            topItem.second = topItem.second + restTopItem.second;
+            store.pop();
+        }
+        store.push(topItem);
+        return topItem.second;
+    }
+    
+    int next(int price) {
+        store.push({price, 1});
+        return restructureStore();
+    }
+};
+
+/**
+ * Your StockSpanner object will be instantiated and called as such:
+ * StockSpanner* obj = new StockSpanner();
+ * int param_1 = obj->next(price);
+ */