var function copyFile() {
var folder=DriveApp.getFolderById('your folder id');
getFnF(folder);
}
function getFnF(folder) {
var srcFile=DriveApp.getFileById('your file id');
var subfolders=folder.getFolders()
while(subfolders.hasNext()) {
var subfolder=subfolders.next();
srcFile.makeCopy(srcFile.getName(),subfolder);
getFnF(subfolder);
}
}