SOLUTION FOR FUNCTION. 1) Write a program to display Hello 10 times. Create user-defined function message().

Transcription

1 SOLUTION FOR FUNCTION 1) Write a program to display Hello 10 times. Create user-defined function message(). #include <stdio.h> #include <conio.h> void message(int); int i; for (i=1;i<=10;i++) message(i); void message (int x) printf ("\n [%d] Hello",x); [1] Hello [2] Hello [3] Hello [4] Hello [5] Hello [6] Hello [7] Hello [8] Hello [9] Hello [10] Hello Explanation In the above program user-defined function message() is defined. This function displays message Hello when invoked. This function is invoked 10 times and 10 times message is displayed. 2) Write a user-defined function for following tasks. a) Clearing the screen. #include <stdio.h> #include <conio.h> void cls(void); int i; for (i=0;i<1000;i++)

2 printf ("%d",i); getche(); cls(); void cls () int i; gotoxy(1,1); for (i=1;i<=250;i++) printf ("\t"); Explanation In the above program the first for loop fills the entire screen with numbers. The cls() user-defined function is used to clear the screen. The for loop used in the function cls() uses \t (tab) to clear the screen. b) Display character at specified row and column number. int r,c; char ch; void at(int,int,char); printf ("\n Enter row and column : "); scanf ("%d %d",&r,&c); printf ("\n Enter a character : "); ch=getche(); at(r,c,ch); void at ( int r,int c, char ch) gotoxy(c,r); putch(ch); Enter row and column: 8 1 Enter a character : c C Explanation In the above program the character that is to be displayed, row and column number are entered. All these values are passed to function at(). The gotoxy() statement is used to position the character at given position.

3 c) Display horizontal line with given symbol. char ch; void line(char); printf ("\n Enter a symbol : "); ch=getche(); printf ("\n"); line(ch); void line ( char ch) int i; for (i=0;i<80;i++) putch(ch); Enter a symbol : Explanation In the above program a character is passed to function line (). Using for loop 80 times the character is displayed on the screen. 3) Write a user-defined function for performing the following tasks. a) Square of a number. void main() int x,s; int sqr(int); printf ("\n Enter a Number : "); scanf ("%d",&x); s=sqr(x); printf("\n Square of %d is = %d",x,s); sqr (int x) return (x*x);

4 Enter a Number: 4 Square of 4 is = 16 Explanation In the above program the function sqr() is defined. A number entered is passed to this function. The function calculates the square of the number and returns it. b) Area of a square. int s; int area(int ); printf ("\n Enter a side : "); scanf ("%d",&s); printf ("\n Area= %d",area(s)); int area ( int c) return (c*c); Enter a side: 3 Area= 9 Explanation: In the above program the function area () is defined. The length of side is entered and passed to function. The function area () calculates area and returns it. c) Conversion of decimal number to binary. int j,n[10]=0,k=0; int binary(int *); printf ("\n Enter a Number : "); scanf ("%d",&j); while (j) n[k]=binary(&j); k++;

5 printf ("\n Binary equivalent is : "); for (k=9;k>=0;k--) printf ("%d",n[k]); int binary (int *b) int k=*b%2; *b=*b/2; return k; Enter a Number: 12 Binary equivalent is: Explanation In the above program an integer is entered. The numbers is passed to function binary() by reference. By modulus operation with two, remainders are obtained and return to main(). In main(), they are stored in array. We get the complete binary number by display the array elements in descending order. d) Reverse the number. int s; void reverse(int); printf ("\n Enter a Number : "); scanf ("%d",&s); printf ("\n Reverse Number : "); reverse(s); void reverse ( int c) while (c) printf ("%d",c%10); c=c/10; Enter a Number : 234 Reverse Number : 432 Explanation In the above program a number is entered and passed to function reverse(). Using while () loop digits are separated and displayed.

6 1) Write a program to calculate average temperature of five days. Create temp() function. void main() float a,b,c,d,e,avg; float temp(float,float,float,float,float); printf ("\n Enter a temperature of five days : "); scanf ("%f %f %f %f %f",&a,&b,&c,&d,&e); avg=temp(a,b,c,d,e); printf("\n Average Temperture = %g",avg); float temp (float a,float b,float c, float d, float e) return ((a+b+c+d+e)/5); Enter a temperature of five days : Average Temperature = Explanation In the above program five float numbers are entered. They are passed to function temp(). Sum of numbers is calculated and divided by 5 to get average. The average obtained is returned and displayed. 2) Write a program to count for how many times a function is called. Create a userdefined function. int c=0; int count(void); c=c+count(); c=c+count()+count(); printf ("\n The function count () is called for %d times",c); int count ( void) return 1;

7 The function count () is called for 3 times Explanation In the above program function count() is invoked. This function returns value 1. This value is added to variable c. Thus, value stored in c indicates number of times function called. 3) Write a program to add return values of three functions. #include<stdio.h> #include<conio.h> int fun1() return 5; int fun2() return 6; int fun3() return 7; int sum; sum = fun1() + fun2() + fun3(); printf ("\n Sum = %d ",sum); Sum = 18 Explanation In the above program three user-defined functions fun1(), fun2() and fun3() are defined. These functions return integer values. These return values are added and sum stored in variable sum. 4) Write a program to increment and display the return value of function. #include<stdio.h> #include<conio.h> void main() int value(void); int x; ++(x=value()); printf ("\n x=%d",x); int value () return (1); X=2 Explanation In the above program the user defined function value() returns an integer. The returned value is assigned to variable x. The value of x is incremented and displayed.

8 5) Write a program to display odd numbers from 1 to 99 using user-defined function. void main() int i; void show (int); for(i=1;i<=100;i+=2) show (i); void show (int k) printf ("%5d",k); Explanation In the above program show() function is used to display the integer. The for loop executed from 1 to 100. In every iteration, the value of loop variable is incremented by two to obtain successive odd numbers. 6) Write a program to calculate square of float values and display it. #include<stdio.h> #include<conio.h> float sq_float(float),a,sq; printf ("\nenter the number :"); scanf ("%g",&a); sq=sq_float(a); printf ("\n The square of %g is : %g",a,sq); float sq_float(float a) return (a*a); Enter the number: 2.5

9 The square of 2.5 is: 6.25 Explanation In the above program the user defined function sq_float() is defined. Its return type is of float type. A float number is passed to this function. The function calculates the square and returns it to main(). 7) Write a program to find prime factors of entered number. For example prime factors of 32 are 2,2,2,2 and2. #include<stdio.h> #include<conio.h> int a,a1[10],k,d=2,l=0; printf ("\nenter the number :"); scanf ("%d",&a); k=a; while(k>1) while(k%d==0) a1[l]=d; l++; k=k/d; d++; printf ("\nthe prime factors of the entered number are :"); for(int i=0;i<l;i++) printf ("\n%d",a1[i]); getch(); Enter the number: 32 The prime factors of the entered number are: Explanation In the above program a number is entered. Using nested while() loop prime factors are calculated. The first while() loop executed until the value of k is greater than one. The second while() loop executes if the entered number is even. In case odd umbers is entered, the inner while loop is skipped and values of divisor (d) is incremented to get next factor. Thus, factors are found.

10 8) Write a program to find highest and lowest common factors of the two numbers. For example, the highest and lowest common factors for 50 and 100 are 5 and 2 respectively. #include<stdio.h> #include<conio.h> int a,k,d=2,l=0,max=0, min=9; printf ("\nenter the number :"); scanf ("%d",&a); k=a; while(k>1) while(k%d==0) if (d>max) max=d; if (d<min) l++; min=d; k=k/d; d++; printf ("\n Highest factor : %d",max); if (l>0) printf ("\n Lowest factor : %d",min); else printf ("\nthe number itself is highest and lowest factor"); getch(); Enter the number: 100 Highest factor: 5 Lowest factor: 2 Explanation The above program is same as last. Here, only highest and lowest factors are displayed. In the inner while loop using if() statements highest and lowest factors are detected and stored in the variable max and min. For repetitive operation, user can insert the entire program inside the for loop.

11 9) Write a program to compute the total amount payable with annual interest for given number of years. The inputs are principle amount, rate of interest and number of years. Attempt the program with and without recursion method. #include<stdio.h> #include<conio.h> float interest(float,float,int); int year; float amt,roi,total; printf ("\nenter the amount, rate of interest and years : "); scanf ("%f %f %d",&amt,&roi,&year); total=interest (amt,roi,year); printf ("\n Total Amount =%g",total); getche(); float interest ( float amt, float roi, int year) float r=roi/100.00; float t=r*amt*year; printf ("\n Interest : %g",t); amt=amt+t; return amt; Enter the amount, rate of interest and years : Interest: 40 Total Amount: 1040 Explanation In the above program user defined function interest () is defied. The amount, rate of interest and number of years are entered and passed to function. The function interest () calculates interest and adds to total amount. The total amount returned by function interest () is displayed. 10) Write a program to calculate the result of following with recursive calls of function. a) x= n # include <process.h> int s=0,n;

12 int num(int); printf ("\n Enter a number : "); scanf ("%d",&n); s=num(n); printf ("\n s=%d",s); getch(); int num (int n) static int s; s=s+n; printf (" %d ",n); if (n>0) num(--n); return s; Enter a number: s=10 Explanation In the above program an entered number is passed to function num (). The num () function calls itself and passed value of n as argument. Each time value of n is decremented and then passed. The sum of numbers is taken in the static variable s. When the number becomes zero, then the recursion is stopped and sum is returned. b) x=1!+2!+3! n # include <process.h> int fact(int); int s=0,n; int num(int); printf ("\n Enter a number : "); scanf ("%d",&n); s=num(n); printf ("\n Total sum of factorials=%d",s); getch(); int num (int n) int f; static int s;

13 f=fact(n); s=s+f; printf ("\nfactorial of %d is %d and sum is %d ",n,f,s); if (n>0) num(--n); return s; fact (int x) int f=1,j; for (j=1;j<=x;j++) 111 f=f*j; return f; Enter a number : 5 Factorial of 5 is 120 and sum is 120 Factorial of 4 is 24 and sum is 144 Factorial of 3 is 6 and sum is 150 Factorial of 2 is 2 and sum is 152 Factorial of 1 is 1 and sum is 153 Factorial of 0 is 1 and sum is 154 Total sum of factorials=154 Explanation The above program is same as last one. In, addition here, factorial of successive numbers are calculated and added. The function fact () calculates the factorial of the number and returns. c) x=1+3+5 n # include <process.h> int s=0,n; int num(int); printf ("\n Enter a number : "); scanf ("%d",&n); s=num(n); printf ("\n s=%d",s); getch(); int num (int n)

14 static int s; s=s+n; printf (" %d ",n); if (n>1) num(n-=2); return s; Explanation Enter a number: s=9 Explanation This program is same as exercise (10). Here, the difference between two numbers is two.