#include #include using namespace std; /* * Indexed min priority queue * Supports insertion in O(log N), deletion of any key (regardless of whether * the key is the minimum key or not) in O(log N) and changes to key values * in O(log N), where N is the number of elements currently in the PQ */ class MinIndexedPQ { int NMAX, N, *heap, *index, *keys; void swap(int i, int j) { int t = heap[i]; heap[i] = heap[j]; heap[j] = t; index[heap[i]] = i; index[heap[j]] = j; } void bubbleUp(int k) { while(k > 1 && keys[heap[k/2]] > keys[heap[k]]) { swap(k, k/2); k = k/2; } } void bubbleDown(int k) { int j; while(2*k <= N) { j = 2*k; if(j < N && keys[heap[j]] > keys[heap[j+1]]) j++; if(keys[heap[k]] <= keys[heap[j]]) break; swap(k, j); k = j; } } public: // Create an empty MinIndexedPQ which can contain atmost NMAX elements MinIndexedPQ(int NMAX) { this->NMAX = NMAX; N = 0; keys = new int[NMAX + 1]; heap = new int[NMAX + 1]; index = new int[NMAX + 1]; for(int i = 0; i <= NMAX; i++) index[i] = -1; } ~MinIndexedPQ() { delete [] keys; delete [] heap; delete [] index; } // check if the PQ is empty bool isEmpty() { return N == 0; } // check if i is an index on the PQ bool contains(int i) { return index[i] != -1; } // return the number of elements in the PQ int size() { return N; } // associate key with index i; 0 < i < NMAX void insert(int i, int key) { N++; index[i] = N; heap[N] = i; keys[i] = key; bubbleUp(N); } // returns the index associated with the minimal key int minIndex() { return heap[1]; } // returns the minimal key int minKey() { return keys[heap[1]]; } // delete the minimal key and return its associated index // Warning: Don't try to read from this index after calling this function int deleteMin() { int min = heap[1]; swap(1, N--); bubbleDown(1); index[min] = -1; heap[N+1] = -1; return min; } // returns the key associated with index i int keyOf(int i) { return keys[i]; } // change the key associated with index i to the specified value void changeKey(int i, int key) { keys[i] = key; bubbleUp(index[i]); bubbleDown(index[i]); } // decrease the key associated with index i to the specified value void decreaseKey(int i, int key) { keys[i] = key; bubbleUp(index[i]); } // increase the key associated with index i to the specified value void increaseKey(int i, int key) { keys[i] = key; bubbleDown(index[i]); } // delete the key associated with index i void deleteKey(int i) { int ind = index[i]; swap(ind, N--); bubbleUp(ind); bubbleDown(ind); index[i] = -1; } }; class Interval { public: int start, finish; bool operator < (const Interval& x) const { if (start != x.start) return start < x.start; return finish < x.finish; } } *intervals; int main() { int N, i, j, d, *schedule; scanf("%d", &N); // Number of intervals intervals = new Interval[N]; for (i = 0; i < N; i++) scanf("%d %d", &intervals[i].start, &intervals[i].finish); // sort intervals in non-decreasing order of start times sort(intervals, intervals + N); schedule = new int[N]; MinIndexedPQ pq(N); d = 0; schedule[0] = 0; pq.insert(0, intervals[0].finish); for (i = 1; i < N; i++) { j = pq.minIndex(); if (intervals[i].start >= pq.keyOf(j)) { schedule[i] = j; pq.increaseKey(j, intervals[i].finish); } else { d++; schedule[i] = d; pq.insert(d, intervals[i].finish); } } printf("%d\n", d + 1); // Minimum number of resources required for (i = 0; i < N; i++) // Assignment of resources to each interval printf("%d %d %d\n", intervals[i].start, intervals[i].finish, schedule[i]); return 0; }