Day 23 Interval List Intersections.cpp

PROBLEM:


Given two lists of closed intervals, each list of intervals is pairwise disjoint and in sorted order.

Return the intersection of these two interval lists.

(Formally, a closed interval [a, b] (with a <= b) denotes the set of real numbers x with a <= x <= b.  The intersection
of two closed intervals is a set of real numbers that is either empty, or can be represented as a closed interval.
For example, the intersection of [1, 3] and [2, 4] is [2, 3].)


Example 1:
Input: A = [[0,2],[5,10],[13,23],[24,25]], B = [[1,5],[8,12],[15,24],[25,26]]
Output: [[1,2],[5,5],[8,10],[15,23],[24,24],[25,25]]
Reminder: The inputs and the desired output are lists of Interval objects, and not arrays or lists.
 

Note:

1. 0 <= A.length < 1000
2. 0 <= B.length < 1000
3. 0 <= A[i].start, A[i].end, B[i].start, B[i].end < 10^9




SOLUTION:


class Solution {
public:
    vector<vector<int>> intervalIntersection(vector<vector<int>>& A, vector<vector<int>>& B) {
        
        int i,j,n,m,l,h;
        n=A.size();
        m=B.size();
        
        vector<vector<int>> v;
        
        i=0;
        j=0;
        while(i<n && j<m)
        {
            l=max(A[i][0],B[j][0]);
            h=min(A[i][1],B[j][1]);
            
            if(l<=h)
            {
                v.push_back({l,h});
            }
            
            if(A[i][1]<B[j][1])
                i++;
            else
                j++;
        }
        
        return v;
    }
};