/* Bai tap 1_15 - Tinh dien tich cac hinh hoc */

#include <stdio.h>

#include <conio.h>

#include <math.h>

int menu()

{

int c;

printf("

----- Menu -----");

printf("

1. Hinh tam giac");

printf("

2. Hinh tron");

printf("

3. Hinh vuong");

printf("

4. Hinh chu nhat");

printf("

0. Thoat");

printf("

----------------");

printf("

Chon muc : ");

do {

c = getch();

} while (c>'4' || c<'0');

putc(c, stdout);

return c -'0';

}

void hinhtamgiac()

{

int a, b, c;

float p;

printf("

Nhap vao ba canh tam giac : ");

scanf("%d%d%d", &a, &b, &c);

printf("

Chu vi tam giac = %d", a+b+c);

p = (float)(a + b + c)/2;

printf("

Dien tich tam giac = %lf", sqrt(p*(p-a)*(p-b)*(p-c)));

getch();

}

void hinhtron()

{

int r;

printf("

Nhap vao ban kinh hinh tron : ");

scanf("%d", &r);

printf("

Chu vi hinh tron = %f", 2 * M_PI * r);

printf("

Dien tich hinh tron = %f", M_PI * r * r);

getch();

}

void hinhvuong()

{

int a;

printf("

Nhap vao canh hinh vuong : ");

scanf("%d", &a);

printf("

Chu vi hinh tron = %d", 4 * a);

printf("

Dien tich hinh vuong = %d", a * a);

getch();

}

void hinhchunhat()

{

int a, b;

printf("

Nhap vao cac canh hinh chu nhat : ");

scanf("%d%d", &a, &b);

printf("

Chu vi hinh chu nhat = %d", 2 * (a+b));

printf("

Dien tich hinh chu nhat = %d", b * a);

getch();

}

void main()

{

int chon;

do {

chon = menu();

switch(chon)

{

case 1 : hinhtamgiac();

break;

case 2 : hinhtron();

break;

case 3 : hinhvuong();

break;

case 4 : hinhchunhat();

break;

}

} while (chon != 0);

}