(b) Name the header files for the following inbuilt functions. 1 (i) random() (ii) exit() Ans: (i) stdlib.h (ii) process.h/ stdlib.

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1 HALF YEARLY EXAMINATION Session Class - XII ComputerScience (ANSWER KEY) 1. (a) What is the difference between type casting and type promotion in c++? Explain with example. 2 Type casting is the explicit data type conversion into a lower or higher data type whereas type promotion isimplicit conversion of lower data type into higher data type. Type casting is done by the user whereas type promotion is done by the compiler. Give any suitable example. (b) Name the header files for the following inbuilt functions. 1 (i) random() (ii) exit() (i) stdlib.h (ii) process.h/ stdlib.h ( c) Rewrite the program after correcting the error. Underline each correction 2 #include<iostream.h> class game int p=900,t; ; void main() game() t=10; void initial( int p1, t1) p+=p1 ; t+= t1; voidtrackchange() p++; t++; void status() G game; G.initial(10,5); G.trackchange; G.status(); #include<iostream.h> class game <<t<<endline; XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 1 of 16

2 int p,t; game() t=10; void initial( int p1, intt1) p+=p1 ; t+= t1; voidtrackchange() p++; t++; void status() <<t<<endl; ; void main() game G; G.initial(10,5); G.trackchange(); G.status(); (d) Find the output of the following program. 2 #include<iostream.h> #include<string.h> voidstrdisplay( char *str) inti,j,l=strlen(str); for(i=0;i<l;i++) for(j=0;j<=i;j++) cout<<str[j]; cout<<endl; void main() strdisplay( Bishmila ); B Bi Bis XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 2 of 16

3 Bish Bishm Bishmi Bishmil Bishmila (e) Find the output of the following program. 3 #include<iostream.h> #include<conio.h> struct cuboid intl,b,h; ; void contain(cuboid m) cout<<m.l<< * <<m.b<< * <<m.h<<endl; void main() clrscr(); cuboid p1=10,15,5, p2,p3; ++p1.l; contain(p1); p3=p1; ++p3.b; p3.b++; contain(p3); p2=p3; p2.b +=5; p2.h--; contain(p2); 11*15*5 11*17*5 11*22*4 (f) Mention two ways of defining a constant in c++ with example. 2 XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 3 of 16

4 (i) (ii) by using #define preprocessor #define max 20 by using keyword const cons tint max=20; 2. (a) What is the difference between private and protected data members of a class? 2 As per the class is concern, both private and protected members are same. They can not be accessed by the out siders. But in case of inheritance, protected members are inherited where as private members can not. (b)answer the questions(i) and (ii) after going through the following class. 2 class alpha (i) (ii) int x; ; alpha(int y) x=y; //constructor 1 alpha( alpha &t); //constructor 2 ~alpha(); i) Create an object, such that it invokes constructor 1. ii) Write complete definition for constructor 2. alpha a(5); alpha( alpha &t) x=t.x; ( c) Define a class TEACHER in c++ with the following descriptions 4 Private members: T_no integer T_name character array of size 20 B_sal float // salary Designation character array of size 15 Public members: -function read_data() to read all the details except B _sal. -function display() to display the details. -function allocate() to assign salary(b_sal). Designation B_sal PGT 6500 TGT 5500 PRT 4500 XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 4 of 16

5 class teacher intt_no; chart_name[20]; floatb_sal; char designation[15]; voidread_data(); void display(); void allocate(); ; void teacher::read_data() cout<< enter teacher number ; cin>>t_no; cout<< enter teacher name ; gets(t_name); cout<< enter designation ; gets(designation); void teacher::allocate() if(strcmpi(designation, pgt )==0) b_sal=6500; if(strcmpi(designation, tgt )==0) b_sal=5500; if(strcmpi(designation, prt )==0) b_sal=4500; void teacher::display() cout<< teacher number <<t_no; cout<< \nteacher name <<t_name; cout<< \ndesignation <<designation; cout<< \n basic salary <<b_sal; (d) Answer the questions (i) to (iv) based on the following. 4 class publisher char pub[12]; protected: ; double turnover; void register(); publisher(); void enter(); void display(); XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 5 of 16

6 class branch protected: ; char city[20]; float employee; branch(); voidhaveit(); voidgiveit(); void author: private branch, public publisher ; intacode; charaname[20]; float amount; author(); void start(); void show(); (i) Write the names of data members, which are accessible from objects belonging to class author. (ii) Write the names of all the member functions which are accessible from objects belonging to class branch. (iii) Write the names of all the members which are accessible from member functions of class author. (iv) How many bytes will be required by an object belonging to class author. (i) None (ii) haveit(), giveit() (iii) data members: employee, acode, aname, amount functions: giveit(), haveit(), register(), enter(), display(), start(), show() (iv) (a) Write a function TO DISPLAY MIDDLE ROW AND MIDDLE COLUMN ELEMENTS from a two dimensional array. Function should pass array, number of rows and columns. 3 voidshowmid( int p[][5], int r, int c) if( r%2!=0) XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 6 of 16

7 for(int j=0; j<c; j++) cout<<p[r/2][j]<< ; else cout<< no middle row ; if( c%2!=0) for(inti=0; i<r; i++) cout<<p[i][c/2]<< ; else cout<< no middle column ; (b) An array A[40[10] is stored in the memory along the column with each element requiring 4 bytes of storage. Find out the address location of A[3][6], if memory location of A[30][10] is stored at Row=m=40 Col=n=10 Size=w=4 Address of s[30][10]=9000 I=30, j=10 Address of s[i][j]= B+( (i-0)+(j-0)*m)*w 9000= B+( *40)*4 B= =7280 Address of s[3][6] = 7280+(3 + 6 * 40)*4 = =8252 ( c) Convert the following infix expression into postfix expression using a stack and show the contents of the stack after execution of each operation.p/(q-r)*s+t 2 element operation stack status postfix operation ( push ( P print P / push (/ P XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 7 of 16

8 ( PUSH (/( P Q print (/( PQ - Push - (/(- PQ R print (/(- PQR ) POP AND PRINT (/( PQR- POP AND CANCEL (/ PQR- * POP AND PRINT ( PQR-/ PUSH (* PQR-/ S print (* PQR-/S + POP AND PRINT ( PQR-/S* PUSH ( + PQR-/S* T print (+ PQR-/S*T ) pop and print ( PQR-/S*T+ pop and cancel PQR-/S*T+ ; stop PQR-/S*T+ (d) Evaluate the following postfix expression using stack. Show status of stack for each operation * 15 3 / - ( assume ; is the end of postfix expression) Scanned element operation Stack status Result 4 push 4 10 push push Pop Pop 10 4 Evaluate 10 * 5 Push * Pop 50 4 Pop 4 # Evaluate 4 * 50 Push Push push / Pop Pop Evaluate 15/3 Push Pop XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 8 of 16

9 Pop 200 # Evaluate Push ; Pop and print False # 195 (e) Write a function in C++ to insert and deleteelements into a dynamically allocated queuecontaining student details as given below. 3 struct NODE intadmno; charstu_name[20]; // admission number // student s name NODE *next; ; class Queue NODE *r, *f; Queue() r=null; f=null; void insert(); voiddeleteele(); ~Queue(); ; void queue::insert() node *t=new node; cin>>t->admno; t->stu_name; t->next=null; if(f==null) f=t; r=t; XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 9 of 16

10 else r->next=t; r=t; voiddeletele() node * t; if( f==null) cout<< queue empty ; else t=f; cout<< deleted element is <<t->admno<<t->stu_name; f=f->next; delete t; (f) Write a function SORTPOINTS() in c++ to array of structure game in descending order of points using bubble sort. 3 struct game longpno; //player number charpname[20; //player name long points; ; void arrange( game t[ ], int n) game t1; for(inti=0; i<(n-1); i++) for( j=0; j<(n-1-i); j++) if(t[j].points<t[j+1].points) XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 10 of 16

11 t1=t[j]; t[j]=t[j+1]; t[j+1]=t1; 4. (a) What is the difference between get() and read(). 1 get() is an character input function which retrieves one character at a time. Read() retrieves a block of data called record. (b) What is the difference between app and ate mode of opening a file. 1 app is one of the file opening mode in ofstream where records can be added always at end without disturbing previous records. ate mode is exactly same that of app mode but records may be added at any position. (c)write a function to count and display the number of words containing maximum 3 characters, present in a text file story.txt. 2 b) void countword() intcnt=0; ifstream if1( story.txt ); charch[10]; while(! if1.eof()) if1>>ch; if(strlen( ch)<=3) cnt ++; if1.close(); cout<< number of words <<cnt; XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 11 of 16

12 (d) Given a binary file consumer.dat containing records of the following class 3 class consumer charc_name[20]; charc_add[20]; char area[20]; charc_phone[15]; void ledger(); voiddisp(); intcheckcode(char ac[]) returnstrcmp(area,ac); ; Write a function COPYAREA() in c++, that would copy only those records having area as NORTH from consumer.dat to back.dat. void transfer() ifstream if1; if1.open( consumer.dat,ios::binary); ofstream of1; of1.open( back.dat, ios::binary); consumer p; while(if1.read((char *)&p, sizeof(p))) if(p.checkcode( NORTH )==0) of1.write((char*)&p, sizeof(s)); if1.close(); of1.close(); 5.(a)Find the output of the following assuming all the required header files have been included. 2 void main() int x[]= 10,20,30,40,50; int *p, **q, *t; XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 12 of 16

13 p=x; t=x + 1; q=&t; cout<< *p << ; << **q<< ; << *t++; 10;30;20 (b) Give the output of the following (assume all required header files are included) 2 void main() int array[]=2,3,4,5 ; int *ptr= array; int value=*ptr; cout<<value<< \n ; value=*ptr ++; cout<<value<< \n ; value = *ptr; cout<<value<< \n ; value = * ++ptr ; cout<<value<< \n ; (c ) Find the output of the following program: 3 #include<iostream.h> void main() int X[]=10,25,30,55,110; int *p=x; while(*p <110) if( *p % 3!=0) *p = *p +1; XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 13 of 16

14 else p++; *p = *p +2; for(inti=4; i>=1; i--) cout<< X[i]<< * ; 110*56* 32*26*33 if(i% 3 ==0) cout<<endl; cout<<x[0] * 3<<endl; (d) What will be the output of the following program: 3 #include<iostream.h> #include<ctype.h> #include<conio.h> #include<string.h> voidnewtext( char string[], int&position) char *pointer=string; void main() int length=strlen(string); for( ; position<length-2; position+=2, pointer++) *(pointer+position)=toupper(*(pointer+position)); clrscr(); int location=0; char message[]= dynamic act ; newtext ( message,location); cout<<message<< # <<location; DynAmiC act#10 6. (a) Differentiate between Primary key and unique key in the context of RDBMS. 2 XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 14 of 16

15 Primary key: It is the key or combination of keys through which we can identify a unique record. Only one primary key is possible in each table. Primary key value may not be NULL. Unique key: It is more or less similar to primary key. But more than one unique key possible and value may be NULL also. (b) Consider the following tables WORKER and DESIG. Write SQL commands for the statements (i) (ii) (iii) (iv) (v) (vi) (vii) (i) to (iv) and give outputs for queries (v) to (viii) 8X1=8 WORKER ID FIRSTNAME LASTNAME CITY 102 Sam Tones Paris 105 Sarah Ackerman New York 144 Manila Sengupta New delhi 210 George Smith Howard 255 Mary Jones Losantiville 300 Robert Samuel Washington 335 Henry William Boston 403 Ronny Lee New York 451 Pat Thompson Paris DESIG ID SALARY BENEFIT DESIGNATION Manager Director Manager Manager Clerk Clerk Clerk Salesman Salesman Display detailsof all employees living in New York from WORKER table. Display contents of WORKER table in descending order of LASTNAME. To display the FIRSTNAME, LASTNAME, total salary(salary + BENEFIT) of all Clerks. To display the minimum SALARY among Managers and Clerks from table DESIG. SELECT FIRSTNAME, SALARY FROM WORKER, DESIG WHERE DESIGNATION= Manager AND WORKER.ID = DESIG.ID; SELECT COUNT(DISTINCT DESIGNATION) FROM DESIG; SELECT DESIGNATION, SUM(SALARY) FROM DESIG GROUP BY DESIGNATION HAVING COUNT(*) <3; XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 15 of 16

16 (viii) SELECT SUM(BENEFIT) FROM DESIG WHERE DESIGNATION= Salesman ; (i) Select * from worker where city= New York ; (ii) Select * from worker order by lastnamedesc; (iii) Select firstname, lastname, salary+benefit total salary from worker, design Where worker.id=design.id and designation= clerk ; (iv) Select designation, min(salary) from design group by designation Having designation in( managers, clerks ); (v) Firstname salary Sam Manila George (vi) 4 (vii) DESIGNATION SUM(SALARY) Director Salesman XII/COMPUTER SCIENCE/HALF YEARLY / /Answer Key Page 16 of 16

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Code No. 91 Please check that this question paper contains 11 printed pages. Code number given on the right hand side of the question paper should be written on the title page of the answer-book by the