// 881. Boats to Save People #include #include /* * given an array 'people' where 'people[i]' is the weight of the i'th 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 person */ int cmp(const void *a, const void *b) { return *(int *)a - *(int *)b; } int numRescueBoats(int *people, int people_size, int limit) { qsort(people, people_size, sizeof(int), cmp); int max_weight = people_size - 1, min_weight = 0, ans = 0; while (min_weight <= max_weight) { if (people[min_weight] + people[max_weight] <= limit) { min_weight++; max_weight--; } else max_weight--; ans++; } return ans; } int main() { int p1[] = {1, 2}, p2[] = {3, 2, 2, 1}, p3[] = {3, 5, 3, 4}; printf("%d\n", numRescueBoats(p1, 2, 3)); // expect: 1 printf("%d\n", numRescueBoats(p2, 4, 3)); // expect: 3 printf("%d\n", numRescueBoats(p3, 4, 5)); // expect: 4 }