Exercise-3.cpp

//Expected Time Complexity: O(logN)
//Hint: Binary Search


#include<bits/stdc++.h>
using namespace std;


int lowerBound(vector<int> A, int Val) {
    
    int sz = A.size();
    
    int l = 0, r = (sz-1);
    
    int answer = -1;
    
    while (l <= r) {
        int mid = (l + r) / 2;
        if (A[mid] > Val) {
            r = mid-1;
        }
        else {
            answer = A[mid];
            l = mid+1;
        }
    }
    
    return answer;
    
}