#include<windows.h>
using namespace std;
int main() {
    HWND hwnd = NULL;
    bool hidden = false;
    while (true) {
        if (GetAsyncKeyState('C') & 1) {
            if (!hwnd) hwnd = GetForegroundWindow();
            if (hwnd) {
                hidden = !hidden;
                ShowWindow(hwnd, hidden ? SW_HIDE : SW_SHOW);
                if (!hidden) hwnd = NULL;
            }
        }
        Sleep(50);
    }
    return 0;
}