Problem:
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Areas on the Cross-Section Diagram

Your task is to simulate a flood damage.

For a given cross-section diagram, reports areas of flooded sections.

Assume that rain is falling endlessly in the region and the water overflowing from the region is falling in the sea at the both sides.
For example, for the above cross-section diagram, the rain will create floods which have areas of 4, 2, 1, 19 and 9 respectively.

Input

A string, which represents slopes and flatlands by '/', '\' and '_' respectively, is given in a line. For example, the region of the above example is given by a string "\\///\_/\/\\\\/_/\\///__\\\_\\/_\/_/\".

output

Report the areas of floods in the following format:

$A$

$k$ $L_1$ $L_2$ ... $L_k$

In the first line, print the total area $A$ of created floods.

In the second line, print the number of floods $k$ and areas $L_i (i = 1, 2, ..., k)$ for each flood from the left side of the cross-section diagram. Print a space character before $L_i$.

Constraints

$1 \leq$ length of the string $\leq 20,000$

Sample Input 1

\\//

Sample Output 1

4
1 4

Sample Input 2

\\///\_/\/\\\\/_/\\///__\\\_\\/_\/_/\

Sample Output 2

35
5 4 2 1 19 9

Solution in JAVA (judge verdict: Accepted)

import java.util.Scanner;

class Main {

  static intStack stack = new intStack(20000);
  static Scanner scan;

  static public void main(String[] args){
    // get from std in
    scan = new Scanner(System.in);
    String input = scan.nextLine();

    // calc : total area
    int sum = 0;
    Tuple[] lines = new Tuple[10000];
    int n = 0;
    for(int i = 0; i < input.length(); i++) {
      switch(input.charAt(i)) {
        case '\\':
        stack.push(i);
        break;
        case '/':
        if (!stack.isEmpty()){
          int tmp = (Integer)stack.pop();
          sum += i - tmp;
          lines[n] = new Tuple(tmp, i);
          n++;
        }
        break;
        default:
        break;
      }
    }
    // print : total area
    System.out.println(sum);

    // calc : each floods area
    int[] area = new int[n];
    int count = 0;
    for(int i = 0; i < n; i++) {
      int min = lines[i].tail;
      int index = i;
      for(int j = i+1; j < n; j++) {
        if(min > lines[j].tail) {
          min = lines[j].tail;
          index = j;
        }
      }
      for(int j = i; j <= index; j++){
        area[count] += lines[j].head - lines[j].tail;
      }
      count++;
      i = index;
    }

    if(count > 0){
      System.out.printf("%d ", count);
      for(int i = 0; i < count-1; i++){
        System.out.printf("%d ", area[i]);
      }
      System.out.printf("%d\n", area[count-1]);
    } else {
      System.out.printf("%d\n", count);
    }
  }
}

class Tuple {
  public int tail;
  public int head;

  public Tuple(int t, int h){
    this.tail = t;
    this.head = h;
  }
}


class intStack {
  private static int length;
  private static int[] Stack;
  private static int current;

  public intStack(int length) {
    this.length = length;
    this.Stack = new int[length];
    this.current = 0;
  }

  public void push(int data) {
    this.Stack[current] = data;
    current++;
  }

  public int pop() {
    if (current == 0) return 0;
    current--;
    return this.Stack[current];
  }

  public boolean isEmpty(){
    if (current == 0) return true;
    else return false;
  }
}