#includeint menu(){ int rt; char str[256]; printf("1 ****\n"); printf("2 ****\n"); printf("3 ****\n"); printf("4 ****\n"); printf("5 退出程序\n"); printf("请选择,输入选项前面的数字后回车: "); scanf("%s",str); if ( str[0]>='1' && str[0]<='5' ) rt=str[0]-'0'; else rt=0; return rt;}void f1() {}void f2() {}void f3() {}void f4() {}void main(){ int s,loop=1; while ( loop ) { s=menu(); switch ( s ) { case 1: f1(); break; case 2: f2(); break; case 3: f3(); break; case 4: f4(); break; case 5: loop=0; break; default: break; } }}