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.ArrayList;
//import java.util.Random;
import java.util.Scanner;


public class Main {
	static Slope[] data;
	static int[] height;
	static boolean[] mount;

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		String input = sc.next();

//		StringBuffer str2 = new StringBuffer();
//		int n = (int)(Math.random() * 200) + 1;
//		for (int i = 0; i < n; i++) {
//			int mod = (int)(Math.random() * 1000);
//			switch (mod % 3) {
//			case 0:
//				str2.append('/');
//				break;
//			case 1:
//				str2.append('\\');
//				break;
//			case 2:
//				str2.append('_');
//				break;
//			default:
//				assert true;
//			}
//		}
//		String input = str2.toString();
//		System.out.println(input);
		
		data = new Slope[input.length()];
		
		for (int i = 0; i < data.length; i++) {
			char temp = input.charAt(i);
			switch (temp) {
				case '\\':
					data[i] = Slope.DOWN;
					break;
				case '/':
					data[i] = Slope.UP;
					break;
				case '_':
					data[i] = Slope.FLAT;
					break;
				default:
					assert true;
			}
		}

		height = new int[data.length + 1];
		height[0] = 0;
		mount = new boolean [data.length + 1];
		Slope prev = Slope.UP;
		for (int i = 0; i < data.length; i++) {
			height[i + 1] = height[i] + data[i].height;
			if (prev == Slope.UP && data[i] == Slope.DOWN) {
				mount[i] = true;
			}
			if (data[i] != Slope.FLAT) {
				prev = data[i];
			}
		}
		if ( prev == Slope.UP) {
			mount[data.length] = true;
		}

//		int min = Integer.MAX_VALUE;
//		int max = Integer.MIN_VALUE;
//		for (int i = 0; i < height.length; i++) {
//			if (min > height[i]) {
//				min = height[i];
//			}
//			if (max < height[i]) {
//				max = height[i];
//			}
//		}
//		for (int j = max; j >= min; j--) {
//			StringBuffer str = new StringBuffer();
//			for (int i = 0; i < data.length; i++) {
//				if (data[i] == Slope.UP && j == height[i]) {
//					str.append('/');
//				} else if (data[i] == Slope.DOWN && j == height[i] - 1) {
//					str.append('\\');
//				} else if (data[i] == Slope.FLAT && j == height[i]) {
//					str.append('_');
//				} else {
//					str.append(" ");
//				}
//			}
//			System.out.println(str);
//		}

		ArrayList<Integer> result = new ArrayList<Integer>();
		for (int i = 0; i < height.length; ) {
			int from = nextMount(i);
			if (from == -1) {
				break;
			}
			i = from;
			int to = higherMount(from);
			if (to == -1) {
				i++;
				continue;
			}
			result.add(getSquare(from, to));
			i = to;
		}

		int sum = 0;
		StringBuffer str = new StringBuffer();
		str.append(result.size());
		for (int i = 0; i < result.size(); i++) {
			sum += result.get(i);
			str.append(" ");
			str.append(result.get(i));
		}
		System.out.println(sum);
		System.out.println(str);
		
		sc.close();
	}
	
	private static int nextMount(int start) {
		for (int i = start; i < mount.length; i++) {
			if (mount[i] == true) {
				return i;
			}
		}
		
		return -1;
	}
	
	private static int higherMount(int start) {
		// higher than start or highest one
		int higherHeight = height[start];
        int maxHeight = Integer.MIN_VALUE;
        int maxIndex = -1;
        for (int i = start + 1; i < mount.length; i++) {
			if (mount[i] == true && higherHeight <= height[i]) {
				return i;
			}
            if (mount[i] == true && maxHeight < height[i]) {
                maxIndex = i;
                maxHeight = height[i];
            }
        }
         
        return maxIndex;
    }	
	private static int getSquare(int from, int to) {
		int min = Math.min(height[from], height[to]);
		int square = 0;
		for (int i = from; i < to; i++) {
			if (height[i] > min || height[i + 1] > min) {
				continue;
			}
			square += (min - height[i] + min - height[i + 1]);
		}
		return square / 2;
	}
	
	private static enum Slope {
		DOWN(-1), UP(1), FLAT(0);
		
		int height;
		Slope(int height) {
			this.height = height;
		}
	}
}