## Archive for the ‘ Algorithm ’ Category

A method to solve such problems is to consider the rate of change of the angle in degrees per minute. The hour hand of a normal 12-hour analogue clock turns 360° in 12 hours (720 minutes) or 0.5° per minute. The minute hand rotates through 360° in 60 minutes or 6° per minute.

# ΘM= 6M

M= Minute and H = Hour

Angle between Hour and minute handle

# ΘH – ΘM

Co-ordinate of triangle: A(x1, y1), B(x2, y2), C(x3, y3) and Point P (x, y).

## Approach:

1. Calculate the area triangle that is are of triangle ABC. Area A
2. Calculate the area of PAB. Area A1
3. Calculate the area of PBC. Area A2
4. Calculate the area PCA. Area A3
5. If Point P lies outside the triangle than A1+A2+A3 >A.

Area of Triangle: [x1*(y2-y3) + x2*(y3-y1) + x3*(y1-y2)]/2

In above approach, we will have precision problem because we are dividing the result by 2. So to handle this issue, by taking off 2 times of triangle are.

Write a Program to Return Excel Sheet Column Header Name if Input is a Number

input

-11
1
26
52
28
702
703

output

input number -11 is invalid
input number 1 , output alphabet A
input number 26 , output alphabet Z
input number 52 , output alphabet AZ
input number 28 , output alphabet AB
input number 702 , output alphabet ZZ
input number 703 , output alphabet AAA

``` public static string ConvertToAlphabet(int number)
{
int temp = number;
char[] alphabets = new char[] { 'A', 'B', 'C', 'D', 'E',
'F', 'G', 'H', 'I', 'J',
'K', 'L', 'M', 'N', 'O',
'P', 'Q', 'R', 'S', 'T',
'U', 'V', 'W', 'X', 'Y',
'Z' };
string Alphabet = string.Empty;
int Index = 0;

if (number <= 0)
{

Console.WriteLine("input number {0} is invalid", temp);

return string.Empty;
}

if (number < 27)
{

Console.WriteLine("input number {0} , output alphabet {1}"
, temp, alphabets[number - 1]);

return alphabets[number - 1].ToString();
}
while (number > 0)
{
Index = number % 26;
number = number / 26; ;

if (Index == 0)
{
Index = 26;
number = number - 1;
}
Alphabet = alphabets[Index - 1] + Alphabet;

}

Console.WriteLine("input number {0} , output alphabet {1}"
, temp, Alphabet);
return Alphabet;
}```