_1146.java

packagecom.fishercoder.solutions.secondthousand;

importjava.util.*;

publicclass_1146 {
publicstaticclassSolution1 {
publicstaticclassSnapshotArray {
TreeMap<Integer, Integer>[]
snapshots; // using this data structure is much more efficient in terms of
// storage, esp. if snap() calls happen frequently
intsnapId;

publicSnapshotArray(intlength) {
snapshots = newTreeMap[length];
snapId = 0;
for (inti = 0; i < length; i++) {
snapshots[i] = newTreeMap<>();
snapshots[i].put(0, 0);
 }
 }

publicvoidset(intindex, intval) {
snapshots[index].put(snapId, val);
 }

publicintsnap() {
returnsnapId++;
 }

publicintget(intindex, intsnapId) {
returnsnapshots[index].floorEntry(snapId).getValue();
 }
 }
 }
}