CS 13A

Prof. Sturm 

HW #2 - variable types, loops, functions

Hand in Part II only.

Part I. What’s the output?

1.

int n,m;                                               out

char c=’p’;

char d=’s’;

n=c;

m=d;

cout<<m-n;

2.

int m=3,n=5:                                       out

            while(m+n<14){

            if (m<n)

                        m=n;

            else

                        n=n+1;

            m=m+1;

cout<<m<<” “<<n<<” “<<endl;

}

3.

            for(j=0;j<100;j++){                            out

if (j%24!=0)

            continue;

cout<<j<<endl;

            }

4.

            for(s=0;s<3;s++){                               out

for(t=0;t<3;t++)

cout<<”*”;

cout<<”\n”;

            }

cout<<endl;

5.

int prod(int a,int b,int c){                                            out

cout<<”hello”<<endl;

return(a*b*c);

            }

int prod(int a,int b){

cout<<”hi”<<endl;

                        return(a*b);

            }

            void main(){

cout<<prod(5,6)<<endl;

cout<<prod(2,3,4)<<endl;

            }

6.

            void printchar(char c, int n = 10);                               out

void main(){

printchar(‘*’,5);

printchar(‘&’);

}//end main

void printchar(char c, int n){

for(j=0;j<n;j++)

cout<<c;

cout<<endl;

            }//end printchar

7.

            /* global vs local variables */

int x = 5;

            void func1(){

x=x+3;

cout<<x<<endl;

                        return;

            }

            void func2(int x){

                        x=x+1;

cout<<x<<endl;

            }

            void main(){

int x=10;

                        func2(5);

                        x=x+1;

func1();

func1();

cout<<x<<endl;

            }

            8.

            /* static variables */ 

            void func(){                                                                out

int a=0;

                        static int b=0;

                        a=a+1;

                        b=b+1;

cout<<a<<” “<<b<<” “<<endl;

            }

            void main(){

                        for(int i=1;i<3;i++){

func();

                        }

            }

Part II – Write the three functions: sqrt(), sqrt2(), and sqrt3(). Write a main procedures that call each function. Hand in the source code and the output.

1.      Write a void function sqrt(double num) that finds and displays the square root of num. Write a main procedure that calls the function.

2.      Write a double function sqrt2(double num).  Function sqrt2() finds and returns the square root of num. Write a main procedure that calls the function and displays the square root.

3.      Write a void function sqrt3(double num,double &sqrt).  Function sqrt3 places the square root of num in reference parameter sqrt.  Write a main procedure that calls sqrt3() and then displays the square root.