需要帮助理解一个单词混杂循环

Question

这段代码是一个混杂单词的程序的一部分。 我需要帮助来了解for循环的工作方式并创建混乱的单词。 例如，如果theWord =“ apple”，输出将类似于：plpea。 所以我想知道在for循环中发生了什么，以产生此输出。

    std::string jumble = theWord;
    int length = theWord.size();
    for (int i = 0; i < length; i++)
    {
        int index1 = (rand() % length);
        int index2 = (rand() % length);
        char temp = jumble[index1];
        jumble[index1] = jumble[index2];
        jumble[index2] = temp;
    }
    std::cout << jumble << std::endl;

Answer 1

我将在for循环的每一行添加注释：

for (int i = 0; i < length; i++) // basic for loop syntax. It will execute the same number of times as there are characters in the string
{
    int index1 = (rand() % length); // get a random index that is 0 to the length of the string
    int index2 = (rand() % length); // Does the same thing, gets a random index
    char temp = jumble[index1]; // Gets the character at the random index
    jumble[index1] = jumble[index2]; // set the value at the first index to the value at the second
    jumble[index2] = temp; // set the value at the second index to the vaue of the first
    // The last three lines switch two characters
}

您可以这样想：对于字符串中的每个字符，请切换字符串中的两个字符。 同样，％（或模运算符）也只剩下余数。 了解模运算符％

同样重要的是要了解myString [index]将返回该索引处的任何字符。 例如：“ Hello world” [1] ==“ e”