Tag: draw

C Program To Draw Pyramid of Numbers, using For Loop

Lets write a C program to draw / display / print a four row pyramid formed from numbers 1 to 10.

Related Read:
Nested For Loop In C Programming Language
C Program To Draw Pyramid of Numbers, using While Loop

Video Tutorial: C Program To Draw Pyramid of Numbers, using For Loop


[youtube https://www.youtube.com/watch?v=Z-uVxVnXqgE]

YouTube Link: https://www.youtube.com/watch?v=Z-uVxVnXqgE [Watch the Video In Full Screen.]

Source Code: C Program To Draw Pyramid of Numbers, using For Loop

#include<stdio.h>
int main()
{
    int num = 4, row, col, space, count = 1;
    float i = -7;


    for(row = 1; row <= num; row++)
    {
        for(space = i; space <= (num-row); space++)
        {
            printf(" ");
        }
        for(col = 1; col <= row; col++)
        {
            printf(" %d ", count++);
        }
        i += 0.8;

        printf("\n");
    }

    return 0;
}

Output

                    1
                  2  3
                 4  5  6
               7  8  9  10

Logic To Draw Pyramid of Numbers, using For Loop

Here we already know that the Pyramid we need to print has 4 rows and is formed of numbers 1 to 10.

Outer for loop selects the row number and the number of elements to be printed for that particular selected row. For example, 1st row has 1 element. 2nd row has 2 elements. 3rd row has 3 elements and so on. So the row number and the number of elements in that particular row are always the same.

First inner for loop prints the adequate spacing required for the pyramid. Second inner for loop prints the actual numbers.

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

C Program To Draw Pyramid of Stars, using For Loop

Lets write a C program to draw / print / display a pyramid / triangle formed from stars, using nested for loop.

Related Read:
Nested For Loop In C Programming Language
C Program To Draw Pyramid of Stars, using While Loop

Expected Output for the Input

User Input:
Enter no of rows of Pyramid
5

Output:

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

Pyramid With 20 Rows
pyramid of stars

Video Tutorial: C Program To Draw Pyramid of Stars, using For Loop


[youtube https://www.youtube.com/watch?v=omDJLEDBZNw]

YouTube Link: https://www.youtube.com/watch?v=omDJLEDBZNw [Watch the Video In Full Screen.]

Logic To Draw Pyramid of Stars, using For Loop

If num = 5;

First Iteration of outer for loop
row = 1;

1st inner for loop
condition:
num – row;
= 5 – 1
= 4
Four spaces gets printed.

2st inner for loop
condition:
2 * row – 1;
= 2 * 1 – 1;
= 2 – 1
= 1
One star gets printed.

Second Iteration of outer for loop
row = 2;

1st inner for loop
condition:
num – row;
= 5 – 2
= 3
Three spaces gets printed.

2st inner for loop
condition:
2 * row – 1;
= 2 * 2 – 1;
= 4 – 1
= 3
Three stars gets printed.

Third Iteration of outer for loop
row = 3;

1st inner for loop
condition:
num – row;
= 5 – 3
= 2
Two spaces gets printed.

2st inner for loop
condition:
2 * row – 1;
= 2 * 3 – 1;
= 6 – 1
= 5
Five stars gets printed.

Forth Iteration of outer for loop
row = 4;

1st inner for loop
condition:
num – row;
= 5 – 4
= 1
One space gets printed.

2st inner for loop
condition:
2 * row – 1;
= 2 * 4 – 1;
= 8 – 1
= 7
Seven stars gets printed.

Fifth Iteration of outer for loop
row = 5;

1st inner for loop
condition:
num – row;
= 5 – 5
= 0
Zero space gets printed.

2st inner for loop
condition:
2 * row – 1;
= 2 * 5 – 1;
= 10 – 1
= 9
Nine stars gets printed.

Source Code: C Program To Draw Pyramid of Stars, using For Loop

#include<stdio.h>

int main()
{
    int num, row, col, space;

    printf("Enter no of rows of Pyramid\n");
    scanf("%d", &num);

    for(row = 1; row <= num; row++)
    {
        for(space = 1; space <= (num-row); space++)
        {
            printf(" ");
        }
        for(col = 1; col <= (2*row-1); col++)
        {
            printf("*");
        }
        printf("\n");
    }

    return 0;
}

Output 1:
Enter no of rows of Pyramid
5

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

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

C Program To Draw Pyramid of Alphabets, using While Loop

Lets write a C program to draw / print / display a pyramid / triangle formed from uppercase / capital letter English Alphabets, using while loop.

Related Read:
Nested While Loop: C Program
C Program To Draw Pyramid of Stars, using While Loop

Expected Output for the Input

User Input:
Enter the number of rows for Pyramid
5

Output:

    
     A
    BCD
   EFGHI
  JKLMNOP
 QRSTUVWXY

Pyramid With 20 Rows
pyramid of alphabets

Video Tutorial: C Program To Draw Pyramid of Alphabets, using While Loop


[youtube https://www.youtube.com/watch?v=eDPYA_c73I4]

YouTube Link: https://www.youtube.com/watch?v=eDPYA_c73I4 [Watch the Video In Full Screen.]

Logic To Draw Pyramid of Alphabets, using While Loop

We ask the user to enter the maximum number of rows for the pyramid and store it inside the address of variable num. We declare and initialize a variable count to 1(indicating first row of the pyramid).

In the outer while loop we check if count is less than or equal to num. For each iteration of the while loop we increment the value of count by 1. So the count value will have the row number i.e., for each iteration of the outer while loop we select row one by one (to print the alphabets).

Inside first inner while loop we print the adequate number of space for each row. Inside the second inner while loop we actually print the alphabets needed for each row.

At the end the result will be a pyramid with the number of rows as input by the user.

ASCII Value of Capital Letter English Alphabets

ASCII value of A is 65

ASCII value of B is 66

ASCII value of C is 67

ASCII value of D is 68

ASCII value of E is 69

ASCII value of F is 70

ASCII value of G is 71

ASCII value of H is 72

ASCII value of I is 73

ASCII value of J is 74

ASCII value of K is 75

ASCII value of L is 76

ASCII value of M is 77

ASCII value of N is 78

ASCII value of O is 79

ASCII value of P is 80

ASCII value of Q is 81

ASCII value of R is 82

ASCII value of S is 83

ASCII value of T is 84

ASCII value of U is 85

ASCII value of V is 86

ASCII value of W is 87

ASCII value of X is 88

ASCII value of Y is 89

ASCII value of Z is 90

Reference: C Program To Print All ASCII Characters and Code

Source Code: C Program To Draw Pyramid of Alphabets, using While Loop

#include < stdio.h >

int main()
{
    int num, count = 1, i, alphabet = 65;

    printf("Enter the number of rows for Pyramid\n");
    scanf("%d", &num);

    while(count <= num)
    {
        i = 0;
        while(i <= (num-count))
        {
            printf(" ");
            i++;
        }

        i = 0;
        while(i < (2*count-1))
        {
            printf("%c", alphabet);

            if(alphabet == 90)
            {
                alphabet = 64;
            }

            alphabet++;
            i++;
        }
        printf("\n");
        count++;
    }

    return 0;
}

Output
Enter the number of rows for Pyramid
14

              A
             BCD
            EFGHI
           JKLMNOP
          QRSTUVWXY
         ZABCDEFGHIJ
        KLMNOPQRSTUVW
       XYZABCDEFGHIJKL
      MNOPQRSTUVWXYZABC
     DEFGHIJKLMNOPQRSTUV
    WXYZABCDEFGHIJKLMNOPQ
   RSTUVWXYZABCDEFGHIJKLMN
  OPQRSTUVWXYZABCDEFGHIJKLM
 NOPQRSTUVWXYZABCDEFGHIJKLMN

Note: Inside second nested while loop we are checking for the condition – if alphabet is equal to 90(ASCII value of Z), and then reinitializing it to 64(but ASCII value of A is 65), that is because after the if condition is executed we have alphabet++; statement which increments the value of variable alphabet from 64 to 65(which is the ASCII value of A).

Alphabets and ASCII Value
We can even write the code in if else block as shown below:

        i = 0;
        while(i < (2*count-1))
        {
            printf("%c", alphabet);

            if(alphabet == 90)
            {
                alphabet = 65;
            }
            else
            {
                alphabet++;
            }
            i++;
        }

In this case we assign the value of variable alphabet to 65(ASCII value of A) once it has reached a value of 90(ASCII value of Z).

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

C Program To Draw Pyramid of Stars, using While Loop

Lets write a C program to draw / print / display a pyramid / triangle formed from stars, using while loop.

Related Read:
while loop in C programming
Nested While Loop: C Program

Expected Output for the Input

User Input:
Enter no of rows of Pyramid
5

Output:

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

Pyramid With 20 Rows
pyramid of stars

Video Tutorial: C Program To Draw Pyramid of Stars, using While Loop


[youtube https://www.youtube.com/watch?v=pwLx0cELxY4]

YouTube Link: https://www.youtube.com/watch?v=pwLx0cELxY4 [Watch the Video In Full Screen.]

Logic To Draw Pyramid of Stars, using While Loop

We ask the user to enter the maximum number of rows for the pyramid and store it inside the address of variable num. We declare and initialize a variable count to 1(indicating first row of the pyramid).

In the outer while loop we check if count is less than or equal to num. For each iteration of the while loop we increment the value of count by 1. So the count value will have the row number i.e., for each iteration of the outer while loop we select row one by one (to print the stars).

Inside first inner while loop we print the adequate number of space for each row. Inside the second inner while loop we actually print the stars needed for each row.

At the end the result will be a pyramid with the number of rows as input by the user.

Source Code: C Program To Draw Pyramid of Stars, using While Loop

#include<stdio.h>

int main()
{
    int num, count = 1, i;

    printf("Enter no of rows of Pyramid\n");
    scanf("%d", &num);

    while(count <= num)
    {
        i = 0;
        while( i <= (num - count) )
        {
            printf(" ");
            i++;
        }

        i = 0;
        while(i < (2*count-1))
        {
            printf("*");
            i++;
        }

        printf("\n");
        count++;
    }

    return 0;
}

Output 1:
Enter no of rows of Pyramid
5

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

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

Draw Arcs/Circle with Canvas: HTML5

Today lets learn how to use arcs and paths to draw circle.

Arcs are curves that are portions of a circle. A full circle is a 360 degree arc!
A Path is a collection of some lines(or shapes) that once defined can be either filled or stroked.

index.html and myStyle.css files are kept same as illustrated in previous video tutorial: Canvas State: HTML5

Syntax
arc(x, y, r, sA, eA, TF);

arc method takes 6 parameters. x and y are the x-axis and y-axis, which is the center of the circle.
i.e., The x and y parameters determine where the center of the circle will be located on your canvas.

r is the radius of the circle, in pixels.
i.e., the distance of the curve from the center of the circle.

sA is start angle of the circle.
eA is the end angle of the circle.

TF is the direction – which can take 2 values i.e., True or False.

True: negative degrees, counter-clockwise direction.
False: positive degrees, clockwise direction.

Javascript file
myScript.js

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window.onload = canvas;
 
function canvas()
{
var myCanvas = document.getElementById("myCanvas");
 
if( myCanvas && myCanvas.getContext("2d") ) 
{
var context         = myCanvas.getContext("2d");
 
context.lineWidth= 6;
context.beginPath();
 
var degree = 270;
var radian = ( Math.PI / 180 ) * degree;
 
context.arc(100, 100, 50, 0, radian, false);
context.strokeStyle= "red";
context.fillStyle= "blue";
context.stroke();
context.fill();
context.closePath();
 
}
}

Degree to Radian

radians-and-degrees

We convert degrees to radians using a simple mathematical formula:
Radians = (PI / 180 ) * degree;

Draw Arcs/Circle with Canvas: HTML5


[youtube https://www.youtube.com/watch?v=vE0bstctkp4]

YouTube Link: https://www.youtube.com/watch?v=vE0bstctkp4 [Watch the Video In Full Screen.]



Note:
1. By default, direction of drawing the arc is clockwise/positive degrees(i.e., the value of last parameter is false).
2. PI value is 180.
3. 2 * PI is 360!
4. arc method should be passed with radian values and not degrees.