Console.WriteLine(i1 + " " + i2 + " " + i3 + " " + i4 + " " + i5 + " " + i6);
Everything looks correct. Lets run the program. It seems to
work but there is one problem there are too many combinations and
the program does not end (it is so slow, that
Console.Write("Output: "); Chapter 7. Arrays 245 for (int index = 0;
index < array.Length; index += 2) cfw_ array[index] = array[index] *
array[index]; Console.Write(array[index] + " "); / Output: 1 9 25 In
this example we are iterating through all eleme
10. This exercise can be solved in a couple of ways. One of them is the
following: get the first number and check how many times it is repeated
in the array and store this number in a variable. After a repeated number
is found we change its value to int.M
index, we are just iterating through the collection in a way, defined by
the collection itself. For arrays the order of iteration is consecutive from
the first element to 246 Fundamentals of Computer Programming with
C# the last one. The loop variable in
cols) In the example above we initialize a two-dimensional array of type
integer with size of 2 rows and 4 columns. In the outer brackets we place
the elements of the first dimension, i.e. the rows of the array. Each row
contains one dimensional array, wh
we add the next number on right. If we find a sum equal to S, we print
the sum and the sequence to the console. So this solution uses just with
one scan through the elements in the array. 12. a), b), c) Think about
appropriate ways for iterating through t
by 7. If so we call the operator continue, which skips the rest of the
loops body (it skips adding the current number to the sum). If the
number is not divisible by seven, it continues with updating of the sum
with the current number. The result of the ex
all elements of an array of numbers and we will print them: int[] array =
new int[] cfw_ 1, 2, 3, 4, 5 ; Console.Write("Output: "); for (int index = 0;
index < array.Length; index+) cfw_ / Doubling the number array[index] =
2 * array[index]; / Print the n
for-loop (external) from 1 to n (for the lines) and put another for-loop
(internal) in it for the numbers on the current line, which should spin
from 1 to the number of the current line. The 228 Fundamentals of
Computer Programming with C# external loop s
n We will solve the problem with two for-loops. The outer loop will
traverse the lines, and the inner one the elements in them. When we are
on the first line, we have to print "1" (1 element, 1 iteration of the inner
loop). On the second line we have to
exactly K numbers. Can you define a matrix possible[p, n] to keep
whether the number p can be obtained as a sum of the first n numbers
(the numbers ko, k2, , kn-1)? 22. Use dynamic programming to find
the longest increasing subsequence in the input sequen
Console.WriteLine(); First we declare and initialize an array, which we
want to iterate through and print to the console. The array is twodimensional, therefore we use a for- 250 Fundamentals of Computer
Programming with C# loop which will iterate throug
element can be accessed in the following way: matrix[0, 0] matrix[0, 1]
matrix[0, 2] matrix[0, 3] matrix[1, 0] matrix[1, 1] matrix[1, 2] matrix[1,
3] In this example we can access each element using indices. If we
assign the index for rows to row, and the
one-dimensional array of integer numbers using int[], and we declare a
two-dimensional with int[,]. This example shows that: int[,]
twoDimensionalArray; Chapter 7. Arrays 247 Those arrays we will call
two-dimensional, because they have two dimensions. The
dimensional arrays are difficult to understand explained that way.
Therefore we can imagine them as two-dimensional matrices, which
have rows and columns for the dimensions: The rows and the columns of
the square matrices are numbered with indices from 0
declare multidimensional arrays in a way similar to one-dimensional
arrays. Each dimension except the first is marked with comma: int[,]
intMatrix; float[,] floatMatrix; string[,] strCube; In the example above
we create two-dimensional and three-dimension
it! Prime Numbers in an Interval Example Lets consider another
example of nested loops. We set a goal to print on the console all prime
number in the interval [nm]. We will limit the interval by a for-loop
and in order to check for a prime number we will
Arabic numerals in modern times is different from the ten digits
mentioned Chapter 8. Numeral Systems 267 above but in spite of all
they are still referred to the same numeral system the decimal one).
Beside an alphabet, every numeral system has a base. T
Graphs or find information about these algorithms in Internet. Chapter
8. Numeral Systems In This Chapter In this chapter we will take a look
at working with different numeral systems and how numbers are
represented in them. We will pay more attention to
126 84 36 9 1 1 10 45 120 210 252 210 120 45 10 1 1 11 55 165 330 462
462 330 165 55 11 1 Chapter 7. Arrays 257 Exercises 1. Write a
program, which creates an array of 20 elements of type integer and
initializes each of the elements with a value equals to
example through which we will show that we can put even more than
two loops into each other. Our purpose is to find and print all four-digit
numbers of the type ABCD, where: A+B = C+D (we call them lucky
numbers). We will implement it with four for-loops
its body will start, which contains the second (nested) loop. Its variable
will be initialized, its condition will be checked and the code within its
body will be executed, then the variable will be updated and execution
will continue until the condition
we create an array of numbers, which are after that went through with a
foreach loop, and its elements are printed on the console. Then an array
of city names (strings) is created and in the same way it is went through
and its elements are printed on the
a for-loop from 1 to x-1. After that we can repeat the same for x=prev.
By finding and printing the previous element (prev) many times until it
exists, we can find the elements, which compose the longest sequence in
reversed order (from the last to the fi
implementations. Briefly the idea is to find the smallest element and to
place it at position 0 (through swapping) then to find the smallest
number excluding the first and place it at position 1 and so on, until the
entire array is arranged in ascending o
iterate through the array using foreach loop and we print the elements to
the console. The current element on each step is stored in a variable
capital. We get the following result when we execute the code: Sofia
Washington London Paris Multidimensional A
standardized these lines by making them parallel and conformable to the
geometry of the Earth. He introduced a system of geographical longitude
lines, which included 360 degrees and respectively passed from north to
south and pole to pole. In the book "Al
n, n+1, , m if it is prime. At each iteration of the outer for-loop we
check whether its loop variable num is a prime number. The logic by
which we check for a prime number is already familiar to us. At first we
initialize the variable prime with true. Wi
matrix = cfw_ cfw_1, 2, 3, 4, cfw_5, 6, 7, 8, ; We can get the number of the
rows of this two-dimensional array by using matrix.GetLength(0) and
the number of all columns per row with matrix.GetLength(1). So, in this
case matrix.GetLength(0) returns 2 and