c++ - For Loop 函数参数错误

Question

    void Image::setValues(int start_row, int end_row, int start_column, int end_column, Image & source)
{
    int startPosX = start_row;
    int startPosY = start_column;

    for (int row = 0; startPosX < end_row; row++, startPosX++)
        for (int col = 0; startPosY < end_column; col++, startPosY++)
            std::cout << startPosX << "  " << startPosY << std::endl;
}

我这样称呼这个函数

imageTest.setValues(0, 32, 0, 32, imageTest2);

我期望输出 1024 组数字 (32*32) 而不是我得到如下所示的输出。

我做错了什么？

Answer 1

您忘记在内循环开始时初始化 startPosY。

试试这个:

void Image::setValues(int start_row, int end_row, int start_column, int end_column, Image & source)
{
    int startPosX = start_row;
    int startPosY = start_column;

   for (int row = 0; startPosX < end_row; row++, startPosX++) {
        startPosY = start_column;
        for (int col = 0; startPosY < end_column; col++, startPosY++)
            std::cout << startPosX << "  " << startPosY << std::endl;
    }
}