10 Challenging star pattern programs in C

10 Challenging star pattern programs in C

1. Write a C program to print the following pattern:

         *

      *  *

   *  *  *

*  *  *  *

Program:

01	/* This is a simple mirror-image of a right angle triangle */
02

03	#include <stdio.h>
04	int main() {

05	char prnt = '*';
06	int i, j, nos = 4, s;

07	for (i = 1; i <= 5; i++) {
08	for (s = nos; s >= 1; s--) {  // Spacing factor

09	printf("  ");
10	}

11	for (j = 1; j <= i; j++) {
12	printf("%2c", prnt);

13	}
14	printf("\n");

15	--nos;   // Controls the spacing factor
16	}

17	return 0;
18	}

2. Write C program to print the following pattern:

3.  *                   *

4.  * * *           * * *

5.  * * * * *   * * * * *

* * * * * * * * * * *

Program:

01	#include<stdio.h>
02	int main() {

03	char prnt = '*';
04	int i, j, k, s, c = 1, nos = 9;

05	for (i = 1; c <= 4; i++) {
06	// As we want to print the columns in odd sequence viz. 1,3,5,.etc

07	if ((i % 2) != 0) {
08	for (j = 1; j <= i; j++) {

09	printf("%2c", prnt);
10	}

11	for (s = nos; s >= 1; s--) { //The spacing factor
12	if (c == 4 && s == 1) {

13	break;
14	}

15	printf("  ");
16	}

17	for (k = 1; k <= i; k++) {
18	if (c == 4 && k == 5) {

19	break;
20	}

21	printf("%2c", prnt);
22	}

23	printf("\n");
24	nos = nos - 4;  // controls the spacing factor

25	++c;
26	}

27	}
28	return 0;

29

}

6. Write C program to print the following pattern:

7.  *                         *

8.     *                   *

9.  *     *             *     *

10.   *     *       *     *

11.*     *      *      *     *

12.   *     *       *     *

13.*     *             *     *

14.   *                   *

*                         *

Program:

01	#include<stdio.h>
02	int main() {

03	char prnt = '*';
04	int i, j, k, s, p, r, nos = 7;

05
06	for (i = 1; i <= 5; i++) {

07	for (j = 1; j <= i; j++) {
08	if ((i % 2) != 0 && (j % 2) != 0) {

09	printf("%3c", prnt);
10	}

11	else if ((i % 2) == 0 && (j % 2) == 0) {
12	printf("%3c", prnt);

13	}
14	else {

15	printf("   ");
16	}

17	}
18	for (s = nos; s >= 1; s--) {  // for the spacing factor

19	printf("   ");
20	}

21	for (k = 1; k <= i; k++) { //Joining seperate figures
22	if (i == 5 && k == 1) {

23	continue;
24	}

25	if ((k % 2) != 0) {
26	printf("%3c", prnt);

27	}
28	else {

29	printf("   ");
30	}

31	}
32	printf("\n");

33	nos = nos - 2;   // space control
34	}  nos = 1;  // remaining half..

35	for (p = 4; p >= 1; p--) {
36	for (r = 1; r <= p; r++) {

37	if ((p % 2) != 0 && (r % 2) != 0) {
38	printf("%3c", prnt);

39	}
40	else if ((p % 2) == 0 && (r % 2) == 0) {

41	printf("%3c", prnt);
42	}

43	else {
44	printf("   ");

45	}
46	}

47	for (s = nos; s >= 1; s--) {
48	printf("   ");

49	}
50	for (k = 1; k <= p; k++) {

51	if ((k % 2) != 0) {
52	printf("%3c", prnt);

53	}
54	else {

55	printf("   ");
56	}

57	}
58	nos = nos + 2;  // space control

59	printf("\n");
60	}

61	return 0;
62	}

Explanation:
This can be seen as an inverted diamond composed of stars. It can be noted that the composition of this figure follows sequential pattern of consecutive stars and spaces.

In case of odd row number, the odd column positions will be filled up with ‘*’, else a space will be spaced and vice-versa in case of even numbered row.

In order to achieve this we will construct four different right angle triangles

aligned as per the requirement.

 Write a C program to print the following pattern:

15.*   *   *   *   *

16.  *   *   *   *

17.    *   *   *

18.      *   *

19.        *

20.      *   *

21.    *   *   *

22.  *   *   *   *

*   *   *   *   *

Program:

01	#include<stdio.h>
02	int main() {

03	char prnt = '*';
04	int i, j, s, nos = 0;

05	for (i = 9; i >= 1; (i = i - 2)) {
06	for (s = nos; s >= 1; s--) {

07	printf("  ");
08	}

09	for (j = 1; j <= i; j++) {
10	if ((i % 2) != 0 && (j % 2) != 0) {

11	printf("%2c", prnt);
12	} else {

13	printf("  ");
14	}

15	}
16	printf("\n");

17	nos++;
18	}

19	nos = 3;
20	for (i = 3; i <= 9; (i = i + 2)) {

21	for (s = nos; s >= 1; s--) {
22	printf("  ");

23	}
24	for (j = 1; j <= i; j++) {

25
26	if ((i % 2) != 0 && (j % 2) != 0) {

27	printf("%2c", prnt);
28	} else {

29	printf("  ");
30	}

31	}
32	nos--;

33	printf("\n");
34	}

35	return 0;
36	}

23. Write a C program to print the following pattern:

24.          *

25.        * * *

26.      * * * * *

27.    * * * * * * *

28.  * * * * * * * * *

29.    * * * * * * *

30.      * * * * *

31.        * * *

32.          *

33.        * * *

      * * * * *

Program:

01	#include<stdio.h>
02	int main() {

03	char prnt = '*';
04	int i, j, k, s, nos = 4;

05	for (i = 1; i <= 5; i++) {
06	for (s = nos; s >= 1; s--) {

07	printf("  ");
08	}

09	for (j = 1; j <= i; j++) {
10	printf("%2c", prnt);

11	}
12	for (k = 1; k <= (i - 1); k++) {

13	if (i == 1) {     continue;
14	}

15	printf("%2c", prnt);
16	}

17	printf("\n");   nos--;
18	}

19	nos = 1;
20	for (i = 4; i >= 1; i--) {

21	for (s = nos; s >= 1; s--) {
22	printf("  ");

23	}
24	for (j = 1; j <= i; j++) {

25	printf("%2c", prnt);
26	}

27	for (k = 1; k <= (i - 1); k++) {
28	printf("%2c", prnt);

29	}
30	nos++;

31	printf("\n");
32	}

33	nos = 3;
34	for (i = 2; i <= 5; i++) {

35	if ((i % 2) != 0) {
36	for (s = nos; s >= 1; s--) {

37	printf("  ");
38	}

39	for (j = 1; j <= i; j++) {
40	printf("%2c", prnt);

41	}
42	}

43	if ((i % 2) != 0) {
44	printf("\n");

45	nos--;
46	}

47	}
48	return 0;

49

}

34. Write a C program to print the following pattern:

35.     *

36.       * *

37.         * * *

38.           * * * *

39.         * * *

40.       * *

     *

Program:

01	/*
02	This can be seen as two right angle triangles sharing the same base

03	which is modified by adding few extra shifting spaces
04	*/

05	#include <stdio.h>
06	// This function controls the inner loop and the spacing

07	// factor guided by the outer loop index and the spacing index.
08	int triangle(int nos, int i) {

09	char prnt = '*';
10	int s, j;

11	for (s = nos; s >= 1; s--) {    // Spacing factor
12	printf("  ");

13	}
14	for (j = 1; j <= i; j++) {      //The inner loop

15	printf("%2c", prnt);
16	}

17	return 0;
18	}

19
20	int main() {

21	int i, nos = 5;
22	//draws the upper triangle

23	for (i = 1; i <= 4; i++) {
24	triangle(nos, i);    //Inner loop construction

25	nos++;              // Increments the spacing factor
26	printf("\n");  }

27	nos = 7;  //Draws the lower triangle skipping its base.
28	for (i = 3; i >= 1; i--) {

29	int j = 1;
30	triangle(nos, i);  // Inner loop construction

31	nos = nos - j;     // Spacing factor
32	printf("\n");

33	}
34	return 0;

35

}

41. Write a C program to print the following pattern:

42.* * * * * * * * *

43.* * * *   * * * *

44.* * *       * * *

45.* *           * *

46.*               *

47.* *           * *

48.* * *       * * *

49.* * * *   * * * *

* * * * * * * * *

Program:

01	#include <stdio.h>
02

03	int main() {
04	char prnt = '*';

05	int i, j, k, s, nos = -1;
06	for (i = 5; i >= 1; i--) {

07	for (j = 1; j <= i; j++) {
08	printf("%2c", prnt);

09	}
10	for (s = nos; s >= 1; s--) {

11	printf("  ");
12	}

13	for (k = 1; k <= i; k++) {
14	if (i == 5 && k == 5) {

15	continue;
16	}

17	printf("%2c", prnt);
18	}

19	nos = nos + 2;
20	printf("\n");

21	}
22	nos = 5;

23	for (i = 2; i <= 5; i++) {
24	for (j = 1; j <= i; j++) {

25	printf("%2c", prnt);
26	}

27	for (s = nos; s >= 1; s--) {
28	printf("  ");

29	}
30	for (k = 1; k <= i; k++) {

31	if (i == 5 && k == 5) {
32	break;

33	}
34	printf("%2c", prnt);

35	}
36	nos = nos - 2;

37	printf("\n");
38	}

39	return 0;
40	}

50. Write a C program to print the following pattern:

51.* * * * * * * * * * * * * * * * *

52.  * * * * * * *   * * * * * * *

53.    * * * * *       * * * * *

54.      * * *           * * *

55.        * * * * * * * * *

56.          * * * * * * *

57.            * * * * *

58.              * * *

                *

Program:

01	#include <stdio.h>
02	int main() {

03	char prnt = '*';
04	int i, j, k, s, sp, nos = 0, nosp = -1;

05	for (i = 9; i >= 3; (i = i - 2)) {
06	for (s = nos; s >= 1; s--) {

07	printf("  ");
08	}

09	for (j = 1; j <= i; j++) {
10	printf("%2c", prnt);

11	}
12	for (sp = nosp; sp >= 1; sp--) {

13	printf("  ");
14	}

15	for (k = 1; k <= i; k++) {
16	if (i == 9 && k == 1) {

17	continue;
18	}

19	printf("%2c", prnt);
20	}

21	nos++;
22	nosp = nosp + 2;

23	printf("\n");
24	}

25	nos = 4;
26	for (i = 9; i >= 1; (i = i - 2)) {

27	for (s = nos; s >= 1; s--) {
28	printf("  ");

29	}
30	for (j = 1; j <= i; j++) {

31	printf("%2c", prnt);
32	}

33	nos++;
34	printf("\n");

35	}
36

37	return 0;
38	}

59. Write a C program to print the following pattern:

60.      *

61.    * * *

62.  * * * * *

63.* * * * * * *

64.*           *

65.* *       * *

66.* * *   * * *

67.* * * * * * *

68.* * *   * * *

69.* *       * *

70.*           *

71.* * * * * * *

72.  * * * * *

73.    * * *

      *

Program:

01	#include <stdio.h>
02	/*

03	* nos = Num. of spaces required in the triangle.
04	* i   = Counter for the num. of charcters to print in each row

05	* skip= A flag for checking whether to
06	*       skip a character in a row.

07	*
08	*/

09	int triangle(int nos, int i, int skip) {
10	char prnt = '*';

11	int s, j;
12	for (s = nos; s >= 1; s--) {

13	printf("  ");
14	}

15	for (j = 1; j <= i; j++) {
16	if (skip != 0) {

17	if (i == 4 && j == 1) {
18	continue;

19	}
20	}

21	printf("%2c", prnt);
22	}

23	return 0;
24	}

25
26	int main() {

27	int i, nos = 4;
28	for (i = 1; i <= 7; (i = i + 2)) {

29	triangle(nos, i, 0);
30	nos--;

31	printf("\n");
32	}

33	nos = 5;
34	for (i = 1; i <= 4; i++) {

35	triangle(1, i, 0); //one space needed in each case of the formation
36	triangle(nos, i, 1); //skip printing one star in the last row.

37	nos = nos - 2;
38	printf("\n");

39	}
40	nos = 1;

41	for (i = 3; i >= 1; i--) {
42	triangle(1, i, 0);

43	triangle(nos, i, 0);
44	nos = nos + 2;

45	printf("\n");
46	}

47	nos = 1;
48	for (i = 7; i >= 1; (i = i - 2)) {

49	triangle(nos, i, 0);
50	nos++;

51	printf("\n");
52	}

53	return 0;
54	}

74. Write a C program to print the following pattern:

75.* * * * * * * * * * * * * * * * * * * * * * * * *

76.  *           *   *           *   *           *

77.    *       *       *       *       *       *

78.      *   *           *   *           *   *

79.        *               *               *

80.      *   *           *   *           *   *

81.    *       *       *       *       *       *

82.  *           *   *           *   *           *

* * * * * * * * * * * * * * * * * * * * * * * * *

Program:

01	#include <stdio.h>
02

03	/*
04	* nos = Num. of spaces required in the triangle.

05	* i   = Counter for the num. of characters to print in each row
06	* skip= A flag for check whether to

07	*       skip a character in a row.
08	*

09	*/
10

11	int triangle(int nos, int i, int skip) {
12	char prnt = '*';

13	int s, j;
14	for (s = nos; s >= 1; s--) {

15	printf("  ");
16	}

17	for (j = 1; j <= i; j++) {
18	if (skip != 0) {

19	if (i == 9 && j == 1) {
20	continue;

21	}
22	}

23	if (i == 1 || i == 9) {
24	printf("%2c", prnt);

25	}
26	else if (j == 1 || j == i) {

27	printf("%2c", prnt);
28	} else {

29	printf("  ");
30	}  }

31	return 0; }
32	int main() {

33	int i, nos = 0, nosp = -1, nbsp = -1;
34	for (i = 9; i >= 1; (i = i - 2)) {

35	triangle(nos, i, 0);
36	triangle(nosp, i, 1);

37	triangle(nbsp, i, 1);
38	printf("\n");

39	nos++;
40	nosp = nosp + 2;

41	nbsp = nbsp + 2;
42	}

43	nos = 3, nosp = 5, nbsp = 5;
44	for (i = 3; i <= 9; (i = i + 2)) {

45	triangle(nos, i, 0);
46	triangle(nosp, i, 1);

47	triangle(nbsp, i, 1);
48	printf("\n");

49	nos--;
50	nosp = nosp - 2;

51	nbsp = nbsp - 2;
52	}

53	return 0;
54	}