b09 4 local global variable for变量作用域根据在程序中范围不同可以将分为

usingnamespacestd;voidexchange(inta,int{intif(a<{p=a;a=b;b=}}

abint{inta=3,b=5;exchange(a,b);cout<<a<<""<<b<<endl;return0;}

abusingnamespacestd;intexcelnumber=0;voidexcel_count(floatscore{if(score>{

}}int{floatscore=for(inti=0;i<100; cin>>score;}

cout<<excel_count<<endl;return0;usingnamespacestd;voidexchange(inta,int{intif(a<{p=a;a=b;b=}}

abint{inta=3,b=5;exchange(a,b);cout<<a<<""<<b<<endl;return0;}

ab}usingnamespacestd;intexcelnumber=0;voidexcel_count(floatscore{if(score>{

}}int{floatscore=for(inti=0;i<100;{

cin>>score;}

cout<<excel_count<<endl;return0;} usingnamespace inta=0,b=voidexchange( intif(a< {p=a;a=b;b=}}

main( exchange(p=a=p=a=b=exchange(a,exchange(a,cin>>a>>b;exchange();returncout<<a<<"returnusingnamespacestd;inta=0,b=0;voidexchange({intif(a<{

vs. p=a;a=b;b=}

main(

exchange(p=a=bp=a=b=exchange(a,exchange(a,cin>>a>>b;exchange();cout<<a<<""<<b<<endl;return}}usingnamespacestd;inta=0,b=0;

vs.voidexchange(inta,int{intif(a<{p=a;a=b;b=

a,

a,当全局变量与局部变量同名时，当全局变量与局部变量同名时，局部变量将在自己作用域内有效，它将屏蔽同名的全局变量。}int{exchange(a,b);cout<<a<<""<<b<<endl;return0;}usingnamespacestd;inta=0,b=0;voidexchange(inta,int{intif(a<{p=a;a=b;b=

a,

a,当全局变量与局部当全局变量与局部变量同名时，局部变量将在自己作用域内有效，它将屏蔽同名的全局变量}int{cout<<a<<""<<b<<endl;return0;usingnamespacestd;inta=0,b=0;

vs. voidexchange(inta,int{intif(a<{p=a;a=b;b=}

main(

exchange( intexchange(a,exchange(a,exchange(a,b);cout<<a<<""<<b<<return }} usingnamespace inta=0,b=voidexchange(inta,int{intif(