Very Easy to Understand C++ Solution

#include <bits/stdc++.h> 
vector<int> maxOfSubarray(vector<int> nums, int n, int k) 
{
	vector<int> ans;
	for(int i = 0; i<n-k+1; i++){
		int Max=INT_MIN;
		for(int j = 0; j<k; j++){
			Max=max(Max,nums[i+j]);
		}
		ans.push_back(Max);
	}
	return ans;
}

select '[0-5>' as bin,
count() as total from sessions where duration >= 0 and duration<300
union 
select '[5-10>' as bin,
count(1)as total from sessions where duration >= 300 and duration<600
union
select '[10-15>' as bin,
count(1) as total from sessions where duration >= 600 and duration <900
union
select '15 or more' as bin,
count(1) as total from sessions where duration >= 900

#include <bits/stdc++.h> 
void helper(vector<vector<int>>&mat, int i, int j,int m, int n, vector<int>&curr, vector<vector<int>>&v){
    curr.push_back(mat[i][j]);
    if(i == m-1 and j == n-1){
        v.push_back(curr);
        curr.pop_back();
        return;
    }
    
    if(i+1 < m) helper(mat,i+1,j,m,n,curr,v);
    if(j+1 < n) helper(mat,i,j+1,m,n,curr,v);
    curr.pop_back();
}
vector<vector <int> > printAllpaths(vector<vector<int> > & mat , int m , int n)
{
    vector<vector<int>>v;
    vector<int> curr;
    helper(mat, 0, 0, m, n, curr, v);
    return v;
}

#include <bits/stdc++.h> 
int partition(vector<int>&arr, int low, int high){
    int pivot = arr[high];
    int i = low-1;
    for(int j = low; j<high; j++){
        if(arr[j]<pivot){
            i++;
            swap(arr[i],arr[j]);
        }
    }
    swap(arr[i+1],arr[high]);
    return i+1;
}

void QuickSort(vector<int>&arr,int low, int high){
    if(low>high)return;
    int pi = partition(arr, low, high);
    QuickSort(arr,low,pi-1);
    QuickSort(arr,pi+1,high);
}
vector<int> quickSort(vector<int> arr)
{
    int n = arr.size();
    QuickSort(arr,0,n-1);
    return arr;
}

int findMinimumCoins(int amount)  {    vector<int>ans, currency = {1, 2, 5, 10, 20, 50, 100, 500, 1000};    for(int i = 8; i>= 0; i--){        while(amount >= currency[i]){            amount -= currency[i];            ans.push_back(currency[i]);        }    }    return ans.size(); }