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structures

header filesarrays

functionsstrings

pointers

dynamic variables

in C

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variables, arrays, atructures

Variables Arrays Structures

int sum; int arr[7]; struct CItem{

char name[21];

float cost;};sum arr[0]

arr[1]

arr[2]

arr[3]arr[4]

arr[5]

arr[6]

name

cost

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application

Representing shopping items as structures

(records)

Difference between types and variables

If int is a type then (after int x;) x is a variable

We can define a structure type and then we

can define variables of that type Type definitions are like blueprints and

variables are like houses

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header files

#define LONGEST_NAME 20+1

struct CItem

{

char name[LONGEST_NAME];float cost;

};

void displayItem(struct CItem item)

{printf("%-20s: %7.2f", item.name, item.cost);

}

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main function

void main(void)

{

struct CItem p1;

strcpy(p1.name, "USB Cable");

p1.cost = 29.95f;displayItem(p1);

printf("\n");

printf("sizeof(struct CItem) = %d bytes\n", sizeof(struct CItem));

printf("sizeof(p1) = %d bytes\n", sizeof(p1));

printf("sizeof(p1.name) = %d bytes\n", sizeof(p1.name));

printf("sizeof(p1.cost) = %d bytes\n", sizeof(p1.cost));

getchar();

}

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output

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populate function

void populate(struct CItem items[], int n)

{

strcpy(items[0].name, "Tripod");

items[0].cost = 12.95f;

strcpy(items[1].name, "Charger");items[1].cost = 22.95f;

strcpy(items[2].name, "HDMI Cable");

items[2].cost = 29.95f;

strcpy(items[3].name, "Ethernet Cable");items[3].cost = 9.95f;

strcpy(items[4].name, "Surge Protector");

items[4].cost = 25.95f;

}

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displayList function

void displayList(struct CItem items[], int n)

{

int i;

printf("%-20s: %7s\n\n", "Name", "Cost");for (i=0; i

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main function

struct CItem list[5];

populate(list, 5);

displayList(list, 5);

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output

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output