CSE Arrays

On February 19, 2015 in Computer Science Engineering my teacher taught the class about Arrays. An Array is essentially a list of data which will contain a certain length of variables. Since the first element in an array is [0] if you want an Array that contains a length of 10 the array should read array[9]. Below is the notes my class took on Arrays.

// arrays!!!

// declare an integer array

// datatype[] name;

int[] array;

// create the array

// name = new datatype[size];

array = new int[10];

// or you can declare and create

int[] array2 = new int[10];

// assign random ints to array

// this loop starts at 0 and runs until we've reached array.length (100)

for(int i = 0; i < array.length; i++){

 // since random() returns a float, we can

 // cast it to an int

 array[i] = (int)random(101);

}

// assign random ints to array

// this loop starts at 0 and runs until we've reached array.length (100)

for(int i = 0; i < array2.length; i++){

 // since random() returns a float, we can

 // cast it to an int

 array2[i] = (int)random(101);

}

// let's check - print out the elements of array

println(array);

print(array);

print("\n"); // print new line

// "\t" <- tab

// "\"" <- "

// "\'" <- '

// "\\" <- \

// double each value stored in array and store it back into array

for(int i = 0; i < array.length; i++){

 array[i] *= 2; // array[i] = array[i] * 2;

}

// print out the elements of array

for(int i = 0; i < array.length; i++){

 println("[" + i + "] " + array[i]);

}

// count how many even numbers are in array2

int numEvens = 0;

for(int i = 0; i < array2.length; i++){

 if(array2[i] % 2 == 0){

   numEvens++;

 }

}

println(array2);

println(numEvens);

// copy everything from array into array2

for(int i = 0; i < min(array.length, array2.length); i++){

 array2[i] = array[i];

}

print(array + " " + array2 + "\n");

boolean isEqual = true;

// int numEqual = 0;

for(int i = 0; i < array.length; i++){

 if(array[i] == array2[i]){

   // numEqual++;

 }

 else{

   isEqual = false;

 }

}

println(array == array2);

// println(numEqual == array.length);

println(isEqual);