else {if(d==1){ y=y-1; m=12; d=31;} } } else {
if(m==2||m==4||m==6||m==8||m==9||m==11) {if(d==1){ m=m-1; d=31;} else d=d-1; } else if(m==5||m==7||m==10||m==12) {if(d==1){ m=m-1; d=30;} else d=d-1; } else if(m==3) {if(d==1){ m=m-1;d=28;} else d=d-1; } else {if(d==1){ y=y-1; m=12; d=31;} } }
cout< cout<<\请输入年y 月m 日d\ cin>>y>>m>>d; data t; t.set(y,m,d); for(i=1;i<=3;i++){ cout<<\进行加一天运算:\ cout<<\进行减一天运算:\ cout<<\ cout<<\请输入选择:\ cin>>choice; if(choice==0) break; switch(choice){ case 1:data v; v.add(y,m,d);break; case 2:data z; z.jian(y,m,d);break; } } return 0; }