int x;

int y;

Pair(int x, int y){

this.x = x;

this.y = y;

}

static final int dx[] = {0,0,1,-1};

static final int dy[] = {1,-1,0,0};

static ArrayList<Pair> unionXY = new ArrayList<>();

static boolean visit[][];

static int map[][];

static int n,l,r,cnt;

static boolean isMove = false;

public static void main(String[] args) throws IOException{

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

StringTokenizer st = new StringTokenizer(br.readLine());

n = Integer.parseInt(st.nextToken());

l = Integer.parseInt(st.nextToken());

r = Integer.parseInt(st.nextToken());

map = new int[n][n];

for(int i=0; i<n; i++) {

st = new StringTokenizer(br.readLine());

for(int j=0; j<n; j++) {

map[i][j] = Integer.parseInt(st.nextToken());

}

}

move();

System.out.println(cnt);

}

static void move() {

while(true) {

isMove = false;

visit = new boolean[n][n]; //새로 BFS 시작할때마다 방문 초기화

for(int i=0; i<n; i++) {

for(int j=0;j<n; j++) {

if(!visit[i][j]){

bfs(i,j); //방문하지 않은상태면 BFS 시작

}

}

}

if(!isMove) break; //국경이동이 없으면 종료.

else cnt++; //국경이동이 있었다면 일수 추가.

}

}

static void bfs(int x, int y) {

Queue<Pair> q = new LinkedList<>();

q.add(new Pair(x,y));

visit[x][y] = true;

unionXY.add(new Pair(x,y));

while(!q.isEmpty()) {

Pair p = q.poll();

x = p.x;

y = p.y;

for(int k=0; k<4; k++) {

int nx = x + dx[k];

int ny = y + dy[k];

if(0<=nx && nx<n && 0<=ny && ny<n) {

if(!visit[nx][ny] && l <= Math.abs(map[x][y] - map[nx][ny]) && Math.abs(map[x][y] - map[nx][ny]) <= r) {

isMove = true;

visit[nx][ny] = true;

unionXY.add(new Pair(nx,ny));

q.add(new Pair(nx,ny));

}

}

}

}

//BFS 가 끝나면 인구이동 결과 맵에 집어넣기

int sum = 0;

for(int i=0; i<unionXY.size(); i++) {

Pair p = unionXY.get(i);

sum += map[p.x][p.y];

}

for(int i=0; i<unionXY.size(); i++) {

Pair p = unionXY.get(i);

map[p.x][p.y] = sum / unionXY.size();

}

unionXY.removeAll(unionXY);

}

}