***** Nhập tgiác tính S, P :

#include <math.h>

typedef struct diem

{

<tab>int Xa,Xb,Xc;

<tab>int Ya,Yb,Yc;

<tab>float a,b,c,P,cv,dt;

}DIEM;

void nhap (DIEM &p);

void xuly (DIEM &p);

void xuat (DIEM p);

void main ()

{

<tab>clrscr ();

<tab>DIEM p;

<tab>nhap (p);

<tab>xuly (p);

<tab>xuat (p);

<tab>getch ();

}

void nhap (DIEM &p)

{

<tab>printf ("

Nhap toa do dinh A:

x = ");

<tab>scanf  ("%d",&p.Xa);

<tab>printf ("

y = ");

<tab>scanf  ("%d",&p.Ya);

<tab>printf ("

Nhap toa do dinh B:

x = ");

<tab>scanf  ("%d",&p.Xb);

<tab>printf ("

y = ");

<tab>scanf  ("%d",&p.Yb);

<tab>printf ("

Nhap toa do dinh C:

x = ");

<tab>scanf  ("%d",&p.Xc);

<tab>printf ("

y = ");

<tab>scanf  ("%d",&p.Yc);

}

void xuly (DIEM &p)

{

<tab>p.a = sqrt( (p.Xa-p.Xb)*(p.Xa-p.Xb) + (p.Ya-p.Yb)*(p.Ya-p.Yb));

<tab>p.b = sqrt( (p.Xa-p.Xc)*(p.Xa-p.Xc) + (p.Ya-p.Yc)*(p.Ya-p.Yc));

<tab>p.c = sqrt( (p.Xb-p.Xc)*(p.Xb-p.Xc) + (p.Yb-p.Yc)*(p.Yb-p.Yc));

<tab>p.P = (p.a+p.b+p.c)/2;

<tab>p.cv= 2*p.P;

<tab>p.dt= sqrt(p.P*(p.P-p.a)*(p.P-p.b)*(p.P-p.c));

}

void xuat (DIEM p)

{

<tab>printf ("

CV = %0.2f

DT = %0.2f",p.cv,p.dt);

}

_____________

**** Phân Số UCLN : Struct

typedef struct phanso

{

<tab>int tu;

<tab>int mau;

}PHANSO;

int UCLN(int m, int n)

{

<tab>while (m!=n)

<tab>{

<tab><tab>if(m>n)

<tab><tab>{

<tab><tab><tab>m-=n;

<tab><tab>}

<tab><tab>else

<tab><tab>{

<tab><tab><tab>n-=m;

<tab><tab>}

<tab>}

<tab>return m;

}

void nhap (PHANSO &x);

void rutgon (PHANSO &x);

void xuat (PHANSO x);

void main ()

{

<tab>clrscr ();

<tab>PHANSO x;

<tab>nhap (x);

<tab>rutgon (x);

<tab>xuat (x);

<tab>getch ();

}

void nhap(PHANSO &x)

{

<tab>printf ("

Nhap Tu So: ");

<tab>scanf ("%d",&x.tu);

<tab>printf ("

Nhap Mau So: ");

<tab>scanf ("%d",&x.mau);

}

void xuat(PHANSO x)

{

<tab>printf ("

Phan so rut gon la: %d/%d",x.tu,x.mau);

}

void rutgon(PHANSO &x)

{

<tab>int u=UCLN(x.tu,x.mau);

<tab>x.tu = x.tu/u;

<tab>x.mau = x.mau/u;

}

___________

**** Khoảng cách từ A => B :

C1 : STRUCT 1

#include <math.h>

typedef struct 

{

<tab>int x1,x2,y1,y2;

<tab>float kc;

}TOADO;

void nhap(TOADO &p);

void kcach(TOADO &p);

void xuat(TOADO p);

void main ()

{

<tab>clrscr();

<tab>TOADO A;

<tab>nhap (A);

<tab>kcach (A);

<tab>xuat (A);

<tab>getch();

}

void nhap(TOADO &p)

{

<tab>printf ("

Nhap toa do diem A:

x1 = ");

<tab>scanf  ("%d",&p.x1);

<tab>printf ("

y1 = ");

<tab>scanf  ("%d",&p.y1);

<tab>printf ("

Nhap toa do diem B:

x2 = ");

<tab>scanf  ("%d",&p.x2);

<tab>printf ("

y2 = ");

<tab>scanf  ("%d",&p.y2);

}

void kcach(TOADO &p)

{

<tab>p.kc = sqrt ((p.x1-p.x2)*(p.x1-p.x2)+(p.y1-p.y2)*(p.y1-p.y2));

}

void xuat(TOADO p)

{

<tab>printf ("

Khoang cach giua hai diem A(%d,%d) va B(%d,%d) la %0.2f don vi",p.x1,p.y1,p.x2,p.y2,p.kc);

}

-------- C2 : Struct 2

#include<iostream.h>

#include<math.h>

typedef struct

{

<tab>float x,y;

}DIEM;

void nhap(DIEM &a);

float k_c(DIEM P, DIEM Q);

void main ()

{

<tab>clrscr ();

<tab>DIEM P,Q;

<tab>cout<<"

Nhap diem P: ";

<tab>nhap(P);

<tab>cout<<"

Nhap diem Q: ";

<tab>nhap(Q);

<tab>float kq;

<tab>kq=k_c(P,Q);

<tab>cout<<"

Khoang cach tu diem P den Q la: "<<kq;

<tab>getch ();

}

void nhap(DIEM &a)

{

<tab>cout<<"

x = ";

<tab>cin>>a.x;

<tab>cout<<"

y = ";

<tab>cin>>a.y;

}

/*void xuat(DIEM a)

{

<tab>cout<<"

hoanh do: "<<a.x<<"

tung do: "<<a.y;

}*/

float k_c(DIEM P, DIEM Q)

{

<tab>return sqrt((P.x-Q.x)*(P.x-Q.x) + (P.y-Q.y)*(P.y-Q.y));

}