How to move a mouse cursor to a particular monitor

movemouse.cpp

#include <windows.h>
#include <stdio.h>
#include <string.h>

RECT monitors[100];
int numMonitors = 0;

BOOL SaveMonitorInfo(
  HMONITOR Arg1,
  HDC Arg2,
  LPRECT Arg3,
  LPARAM Arg4)
{
    monitors[numMonitors++] = *Arg3;
    return TRUE;
}

int main(int argc, char** argv) {
    EnumDisplayMonitors(
        NULL,
        NULL,
        SaveMonitorInfo,
        NULL);

    int whichMonitor = argc > 1 ? atoi(argv[1]) : -1;
    for (int i=0; i < numMonitors; ++i) {
        int x = (monitors[i].right-monitors[i].left)/2 + monitors[i].left;
        int y = (monitors[i].bottom-monitors[i].top)/2 + monitors[i].top;
        if (whichMonitor == i || (whichMonitor < 0
                && monitors[i].left == 0 && monitors[i].top == 0)) {
            printf("moving to monitor #%d\n", i);
            SetPhysicalCursorPos(x, y);
        }
    }
    return 0;
}