# 2. Find Min & Max Answer

``````/*Find the min and max and average of 15 integers that a user will input.
**We will do it now for practice and again when we learn arrays. So you do not have to **keep all fifteen numbers stored in memory.
*/

#include <iostream>

int main()
{
int userInput = 0;
int maxNumber = 0;
int minNumber = 100;
int sumTotal = 0;
float average = 0;

//get the numbers from the user
for(int i = 0; i < 15; i++)
{
std::cout << "Enter a number: ";
std::cin>>userInput;
std::cout << userInput << "\n";
if(userInput > maxNumber)
{
maxNumber = userInput;
}
if(userInput < minNumber)
{
minNumber = userInput;
}
sumTotal = sumTotal + userInput;
}
std::cout << "Maximum number = " << maxNumber << "\n";
std::cout << "Minimum number = " << minNumber << "\n";
average = sumTotal / 15.0;
std::cout << "Average = " << average << "\n";
return 0;
}
``````
``````Maximum number = 107
Minimum number = 14
Average = 63.5333
``````

# 3. Arrays

There is a good case that instead of using arrays, you can use vectors. Vectors are more powerful /versatile than arrays.

`````` /*Goal: Practice array manipulation in C++.
**The user will input 40 integers.
**Put them into an array. Then print the array in the order the numbers were
**entered. Then print in reverse order. Then sort the array in ascending order
**and print it.
*/

#include <iostream>
#include <stdio.h>

int main()
{
int userInput[40];

//Enter the numbers into an array called userInput
for(int i = 0; i < 40; i++)
{
scanf("%d", &userInput[i]);
}
//print the array
std::cout<<"\nThe array\n";
for(int i = 0; i < 40; i++)
{
std::cout << userInput[i] <<" ";
}
//print the array in reverse order
std::cout<<"\n\nThe array in reverse order\n";
for(int i = 39; i >= 0; i--)
{
std::cout << userInput[i] <<" ";
}
//sorting the array
for(int i = 0; i < 40; i++)
{
for(int j = 0; j < 39 - i; j++)
{
if(userInput[j] > userInput[j + 1])
{
int temp;
temp=userInput[j];
userInput[j]=userInput[j + 1];
userInput[j + 1]=temp;
}
}
}
std::cout<<"\n\nThe array sorted\n";
for(int i = 0; i< 40; i++)
{
std::cout << userInput[i] <<" ";
}
return 0;
}
``````
``````The array
43 32 21 23 43 98 90 65 53 42 69 79 82 7 1 63 64 90 87 96 4 55 3 7 2 1 67 89 543 567 985 34 975 890 4567 23 33 9 56 345

The array in reverse order
345 56 9 33 23 4567 890 975 34 985 567 543 89 67 1 2 7 3 55 4 96 87 90 64 63 1 7 82 79 69 42 53 65 90 98 43 23 21 32 43

The array sorted
1 1 2 3 4 7 7 9 21 23 23 32 33 34 42 43 43 53 55 56 63 64 65 67 69 79 82 87 89 90 90 96 98 345 543 567 890 975 985 4567
``````

# 7. Array Searches

`````` #include <iostream>
#include <stdio.h>

int main()
{
int searchKey = 0;
int searchArray[10] = {324,4567,6789,5421345,7,65,8965,12,342,485};
int location = 0;

while(1)
{
std::cout<<"Enter an integer ('-1' to quit): ";
scanf("%d", &searchKey);
std::cout<< searchKey<<"\n";
if(searchKey == -1)
{
break;
}
for(int i = 0; i < 10; i++)
{
if(searchKey == searchArray[i])
{
location = i;
break;
}
location = -1;
}
if(location != -1)
{
std::cout<<searchKey<<" is at location "<<location<<" in the array.\n";
}
else
{
std::cout<<searchKey<<" is not in the array.\n";
}
}
return 0;
}
``````

# 8. MultiDimensional Arrays

``````/*Goal: understand multidimensional arrays in C++*/

#include<iostream>

int main()
{
int array2Dim[2][3] = {0,1,2,3,4,5};
for(int i=0; i<2;i++)
for(int j=0;j<3;j++)
std::cout<<"array2Dim["<<i<<"]["<<j<<"] = " << array2Dim[i][j]<<"\n";
return 0;
}
``````
``````array2Dim[0][0] = 0
array2Dim[0][1] = 1
array2Dim[0][2] = 2
array2Dim[1][0] = 3
array2Dim[1][1] = 4
array2Dim[1][2] = 5
``````

# 9. Multidimensional Arrays Programming Quiz

``````/*Goal: practice using multidimensional arrays.
**Write a program that will accept values for a 4x4 array
**and a vector of size 4.
**Use the dot product to multiply the array by the vector.
**Print the resulting vector.
*/

#include<iostream>

int main()
{
//array dimensions must be known at compile time
//so I used const int to set the row and col numbers
const int row = 4;
const int col = 4;

int arr[row][col];
int vector[row], product[row];
int sum;

//get the values for the array from the user
for(int i=0;i<row;i++)
for(int j=0;j<row;j++)
{
//std::cout<<"arr["<<i<<"]["<<j<<"] = \n";
std::cin>>arr[i][j];
//std::cout<<"arr["<<i<<"]["<<j<<"] ="<<arr[i][j]<<"\n";
}

//getting the values for the vector from the user
for(int i=0; i<row; i++)
{
//std::cout<<"vector["<<i<<"] = \n";
std::cin>>vector[i];
//std::cout<<"vector["<<i<<"] = "<<vector[i]<<"\n";
}
sum = 0;

for(int i=0;i<row;i++)
{
for(int j=0; j<row;j++)
{
sum = (arr[i][j] * vector[i]) + sum;
}
product[i] = sum;
sum=0;
}

for(int i=0;i<row;i++)
{
std::cout<<"product["<<i<<"] = "<<product[i]<<"\n";
}
return 0;
}
``````