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Chapter 9: Arrays

Declaration//datatype array-name [size];int num[5]; declares an array of 5 int

Accessing array components:

num[0] = 12; //stores the value 12 in index 0 of num

int i = 4; num[i] = 38; //stores 38 in num[4]

num[2*i-5] =45; //stores 45 in num[3]

num[1] = num[0]; //stores 12 in num[1]

num[2] = num[0] + num[1];

We can also use the following:const int size=10;

int list[size];

But rememberthat the size must be known before the runtime, i.e.

int size;

coutsize;

int myList[size];illegal

Array initialization during declarationchar M[3]={A, B, C};

Declares an array of 3 char , and this is equivalent to saying:

char M[ ]={A, B, C};

but , we cant say: char M[]; // we must specify the size

num[0]

num[1]

num[2]

num[3]

num[4]

num[0] 12

num[1] 12

num[2] 24num[3] 45

num[4] 38

M[0] A

M[1] B

M[2] C

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Partial assignment:int list[5]={1,2}; declares an array of 5 int, and initialize the first 2 elements to 1 and2, and set the rest elements to zero

int list[10]={0};array of 10 int, and all elements equal to zero

What is the different between the following two statements?int list[4]={2,1};

int list[ ] = {2,1};

The result of the first statement (int list[4]={2,1}; ) is:

But, the result of the second statement (int list[ ] = {2,1};) is:

What is the result of the following statement?

char list[4]={a};

Initialize list[0] to a, and the rest of elements will be space

list[0] 1

list [1] 2

list [2] 0

list [3] 0

list [4] 0

list[0] 2

list [1] 1

list [2] 0

list [3] 0

list[0] 2

list [1] 1

list[0] a

list [1]

list [2]

list [3]

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Processing one-dimensional Arrays

Main operations used for arrays

#include #includeusing namespace std;

int main()

{int size=3, index;

double list[size], sum=0.0, average;

cout

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//finding the largest element in the array

int maxIndex = 0;

int max=list[0];for ( index=1; indexmax)

{maxIndex = index;

max = list[index];

}

cout