Question

Составьте задачу методом обратного хода

Answer 1

Масса однаго пакета 2 кг колл ичество пакетов 4шт масса всех пакетов ?

Answer 2

В 1 день привезли 120 пар обуви. во второй 200 пар обуви. Сколько пар обуви привезли за два дня?
 120+200=320(пар обуви)
  
В 1 день привезли 120 пар обуви. Обувь привезли и во второй день. Всего привезли в магазин 320 пар обуви. Сколько пар обуви привезли во второй день.
  320--120=200(пар обуви) привезли во второй день.
 в первый и во второй день привезли 320 пар обуви. Во второй день привезли 200 пар обуви. Сколько пар обуви привезли в первый день?
  320-200=120(пар обуви)-привезли в первый день.

Я надеюсь что помогла:) Удачи!! ^-^
                                                    \ /

Answer 3

Method of Backtracking Problem

The method of backtracking is a problem-solving technique that involves systematically searching for a solution by exploring all possible options and then "backtracking" or undoing certain steps when a solution is not found. This approach is commonly used in solving problems that involve finding all possible solutions or combinations.

To illustrate the method of backtracking, let's consider the following problem:

Problem: Finding all permutations of a string

Given a string, we want to find all possible permutations of its characters.

Solution:

To solve this problem using the method of backtracking, we can follow these steps:

1. Define a recursive function that takes the current permutation, the remaining characters, and a list to store the permutations. 2. If there are no remaining characters, add the current permutation to the list of permutations. 3. For each remaining character, swap it with the first character, recursively call the function with the updated permutation and remaining characters, and then swap the characters back to their original positions. 4. Repeat step 3 for each remaining character. 5. Return the list of permutations.

Here's an example implementation in Java:

public List findPermutations(String s) {
    List permutations = new ArrayList<>();
    backtrack("", s, permutations);
    return permutations;
}

private void backtrack(String current, String remaining, List permutations) {
    if (remaining.length() == 0) {
        permutations.add(current);
        return;
    }

for (int i = 0; i < remaining.length(); i++) {
        char c = remaining.charAt(i);
        String newCurrent = current + c;
        String newRemaining = remaining.substring(0, i) + remaining.substring(i + 1);
        backtrack(newCurrent, newRemaining, permutations);
    }
}

Example Usage:

String input = "abc";
List permutations = findPermutations(input);
System.out.println(permutations);

Output:

["abc", "acb", "bac", "bca", "cab", "cba"]

In this example, the function `findPermutations` takes a string as input and returns a list of all possible permutations of its characters. The `backtrack` function is called recursively to generate the permutations by swapping characters and exploring all possible combinations.

Please note that this is just one example of using the method of backtracking to solve a problem. The technique can be applied to various other problems as well, depending on the specific requirements and constraints.