c++ - 为什么即使x和y变大了，程序为什么也要增加x和y的值呢？(Why does the program increase the value of the x and the y even after they are bigger, then they should be?)

Question

I'm making a program, that moves a dot, from the startx, starty to endx, endy.

(我正在编写一个程序，该程序将一个点从startx，starty移到endx，endy。)

But it moves continuously, even after the x and the y are bigger than endx and endy.

(但是，即使x和y大于endx和endy，它也会连续移动。)

Here is the code:

(这是代码：)

int x, y;
            x = startx; y = starty;
            if(startx<goalx){
                if (starty < goaly) {
                    while (startx < goalx || starty < goaly) {
                        x += sqrt(2)*speedx;
                        y += sqrt(2)*speedy;
                    }
                }
                else {
                    while (startx < goalx || starty > goaly) {
                        x += sqrt(2)*speedx;
                        y -= sqrt(2)*speedy;
                    }
                }
            }
            else {
                if (starty < goaly) {
                    while (startx > goalx || starty < goaly) {
                        x -= sqrt(2)*speedx;
                        y += sqrt(2)*speedy;
                    }
                }
                else {
                    while (startx > goalx || starty > goaly) {
                        x -= sqrt(2)*speedx;
                        y -= sqrt(2)*speedy;
                    }
                }


            }
            cout << x << ", " << y << endl;

startx, starty, goalx and goaly are user inputs.

(startx，starty，goalx和Goaly是用户输入。)

  ask by Gerg? Szabó translate from so

Answer 1

The control structures depend on startx and starty but these are never changing.

(控制结构取决于startx和starty但它们从未改变。)

Supposedly x and y should be used instead.

(假定应该使用x和y代替。)