int man;
int women;
int child;
for(man = 0 ; man <= 20 ; man++){
for(women = 0;women <= 25 ; women++){
for(child = 0;child <= 30 ; child++){
if(man + women + child == 30 && 3*man + 2*women +child == 50){
System.out.println("男人可能有:"+man + "个t女人可能有:" +women+"个t小孩还可能有:"+child+"个");
}
}
}
}