Solved problem 0881-boats-to-save-people in c++

cpp/0881-boats-to-save-people.cpp

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+/*
+ Given an array people[i] is the weight of the ith person, 
+ and an infinite number of boats where each boat can carry a maximum weight of limit. 
+ Each boat carries at most two people at the same time, provided the sum of the weight of those people is at most limit.
+ Return minimum number of boats to carry every given person.
+
+ sort, while there is people to carry 
+ carry the heaviest and lightest person provided their weight doesn't exceed limit.
+ otherwise, carry the heaviest person only
+
+ Time: O(n)
+ Space: O(1)
+*/
+
+class Solution {
+public:
+ int numRescueBoats(vector<int>& people, int limit) {
+ sort(people.begin(), people.end());
+
+ int boatRequired = 0;
+ int lightestPerson = 0;
+ int heaviestPerson = people.size()-1;
+
+ //WHILE THERE IS SOMEONE TO CARRY
+ while (lightestPerson <= heaviestPerson){
+ if(people[lightestPerson] + people[heaviestPerson] <= limit){
+ --heaviestPerson;
+ ++lightestPerson;
+ }
+ else{
+ --heaviestPerson;
+ }
+ ++boatRequired;
+ }
+
+ return boatRequired;
+ }
+};