1. (a) Write a C program to display the texts Hello, World! on the screen. (2 points)

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1 1. (a) Write a C program to display the texts Hello, World! o the scree. (2 poits) Solutio 1: pritf("hello, World!\"); Solutio 2: void mai() { pritf("hello, World!\"); (b) Write a C program to output a text file that cotais the texts Hello, World! (3 poits) FILE *file = fope("output.txt", "w"); fpritf(file, "Hello, World!\"); fclose(file); 2. Write a C program to compute the summatio of umbers from 1 to where is a positive iteger provided by the user. The program must also prit out the result to the scree. (5 poits) it i,, sum = 0; pritf("please iput a umber: "); scaf("%d\", &); for (i=1; i<=; i++) sum += i; pritf("sum = %d\", sum); 1

2 3. (a) Write a C fuctio for computig the factorial! where is a iteger. This fuctio must have as a argumet ad retur the value of! Recall that 0! 1 ad! 1 2 ( 1) whe is a positive iteger. (2 poits) it factorial(it ) { it fac = 1, i; if ( <2) retur fac; else { for (i=2; i<=; i++) fac *= i; retur fac; (b) Write a C program to estimate the value of the Euler s umber e usig the fiite sum N 1 e! The program must ask the user to iput the value of N, use the fuctio writte i Problem 3a, ad prit the result to the scree (3 poits) 0 it factorial(it ) { // problem 3a it, N; double e = 0; pritf("please eter the value of N: "); scaf("%d\", &N); for (=0; <=N; ++) e += 1/factorial(); pritf("e = %lf\", e); 2

3 4. Write a modified versio of the followig program so that it ca be successfully compiled. (5 poits) iclude stdio.h mai() Solutio: for (i=1; i<=10; i++) { s = si(i); pritf("%d\t%lf\, i, s); #iclude <math.h> it mai() it i; double s; for (i=1; i<=10; i++) { s = si(i); pritf("%d\t%lf\", i, s); 3

4 5. (a) Write a C library (complex.h) for complex arithmetic. This library must cotai the data structure for complex umbers ad the followig complex arithmetic operatios: add, subtract, multiply, divisio, ad complex cojugate. (4 poits) typedef struct { float x, y; Complex; Complex add(complex a, Complex b) { Complex c; c.x = a.x + b.x; c.y = a.y + b.y; retur c; Complex subtract(complex a, Complex b) { Complex multiply(complex a, Complex b) { Complex divisio(complex a, Complex b) { Complex cojugate(complex a) { 4

5 2 5. (b) Write a C program to compute the value of y ax b c where c 3 i i 1 a 1 i, b 2 i, ad. Here. The program must ask the user to provide the real ad imagiary parts of x ad prit out the value of y o the scree. (4 poits) #iclude "complex.h" Complex a, b, c, x, y, om, deom, y3; a.x = 1; a.y = 1; b.x = 2; b.y = -1; c.x = 3; c.y = 1; pritf("eter the real part of x: "); scaf("%f\", &x.x); pritf("eter the imagiary part of x: "); scaf("%f\", &x.y); om = add( multiply(a,x), b); deom = multiply(c,c); y = divisio(om, deom); pritf("y = (%f,%f)\", y.x, y.y); 5

6 6. (a) Write a C program to compute the value of where x 0,0.01,0.02,,1 ad is a iteger (positive, egative, or zero) whose value is obtaied from the user. The program must output the umerical values of x ad x ito a text file ad all the umbers prited i the file must have exactly 4 decimal digits. I other words, the output text file must cotai two colums of umbers. The first colum is the values of x ad the secod colum is the value of x. (4 poits) x #iclude <math.h> float x, x; it ; FILE *file = fope("output.txt", "w"); pritf("please eter the value of : "); scaf("%d\", &); for (x=0; x<=1; x+=0.01) { x = pow(x, ); fpritf(file, "%.4f\t%.4f\", x, x); fclose(file); (b) Write a MATLAB program to read the text file i Problem 6a ad plot the graph of x versus x. (3 poits) load output.txt x = output(:,1); y = output(:,2); plot(x,y); 6

7 7. Aswer the 3 questios o the right-had side of the followig C program it add(it a, it b) { retur a+b; void multiply(it *a, it b) { *a *= b; it a = 1, b = 2, c = 3; c = add(a, b); pritf("%d\", c); (a) What is the output o the scree? (1 poit) 3 a = add(a, c); pritf("%d\", a); (b) What is the output o the scree? (1 poit) 4 multiply(&a, c); pritf("%d\", a); (c) What is the output o the scree? (2 poit) Aswer the 3 questios o the right-had side of the followig C program it add(it a) { static it b = 0; b += a; retur b; it b = 10; pritf("%d\", b); (a) What is the output o the scree? (1 poit) 10 b = add(1); pritf("%d\", b); (b) What is the output o the scree? (2 poit) 1 b = add(1); pritf("%d\", b); (c) What is the output o the scree? (2 poit) 2 7