돌고 돌아 기본

기본 구현 class Trie { public static class Node { private boolean isEnd; private final Node[] next; public Node(int size) { this.isEnd = false; this.next = new Node[size]; } public Node next(int v) { return this.next[v]; } public boolean isEnd() { return isEnd; } } private final char start; private final int size; private final Node root; public Trie(char start, char end) { this.start = start; this...

기본 구현 class Dijkstra { public static final int INF = 987654321; public static class Pair implements Comparable { private final int x; private final int y; public Pair(int x, int y) { this.x = x; this.y = y; } public int getX() { return x; } public int getY() { return y; } @Override public int compareTo(Pair o) { if (this.x == o.x) { return this.y - o.y; } return this.x - o.x; } } private Dijkstr..

최대 공약수(gcd) - 반복 public int gcd(int a, int b) { while (b != 0) { int r = a % b; a = b; b = r; } return a; } 최대 공약수(gcd) - BigInteger.gcd public int gcd(int a, int b) { return BigInteger.valueOf(a).gcd(BigInteger.valueOf(b)).intValue(); } 최소 공배수(lcm) public int lcm(int a, int b) { return (a * (b / gcd(a,b))); }

기본적인 구현 class Dsu { private final int[] parent; public Dsu(int size) { this.parent = new int[size]; for (int i = 0; i < size; i++) { parent[i] = i; } } public int find(int x) { if (parent[x] == x) { return x; } parent[x] = find(parent[x]); return parent[x]; } public boolean union(int x, int y) { int parentX = find(x); int parentY = find(y); if (parentX == parentY) { return false; } parent[parent..