uses crt;

var a,b,c:integer;

begin

clrscr;

readln(a,b,c);

if (a=b) and (b=c) then write('YES')

else write('NO');

readln;

end.

èo lớp 8 khó thế:v

sao ko tham khảo 

#include <iostream>

using namespace std;

int main()
{
    int a, b, c;

    cout << "Nhap a!"; cin >> a;
    cout << "Nhap b!"; cin >> b;
    cout << "Nhap c!"; cin >> c;

    ((a + b) > c && (a + c) > b && (b + c) > a)?

    cout << "Co! Ba So" << " " << a << " " << b << " " << c << " Tao Thanh Ba Do Dai Canh Cua Mot Hinh Tam Giac!" :
    cout << "Khong! Ba So" << " " << a << " " << b << " " << c << " Khong Tao Thanh Ba Do Dai Canh Cua Mot Hinh Tam Giac!";
}

help mik vs 

mik cần gấp 

#include<iostream>

using namespace std; 

int main() { 

double a, b, c; 

cout << "Canh 1: "; cin >> a; 

cout << "Canh 2: "; cin >> b; 

cout << "Canh 3: "; cin >> c; 

if (a > 0 && b > 0 && c > 0) { 

if (a < b + c || b < a + c || c < a + b) { 

cout << "Day la do dai ba canh cua mot tam giac"; 

} else { 

cout << "Day khong phai do dai ba canh cua mot tam giac"; 

} 

}else { 

cout << "Do dai cac canh cua mot tam giac phai lon hon 0";

} 

return 0; 

}

program tamgiac;

uses crt;

var

a,b,c: integer;

begin

clrscr;

write('nhap vao do dai thu nhat:');readln(a);

write('nhap vao do dai thu hai:');readln(b);

write('nhap vao do dai thu ba:');readln(c);

if (a+b>c) or (b+c>a) or(c+a>b) then write ('day la do dai 3 canh cua tam giac')

else write('day ko phai la do dai 3 canh cua tam giac');

readln;

end.

uses crt;

var a,b,c:real;

begin

clrscr;

repeat

write('Nhap a='); readln(a);

write('Nhap b='); readln(b);

write('Nhap c='); readln(c);

until (a>0) and (b>0) and (c>0);

if (a+b>c) and (a+c>b) and (b+c>a) then writeln('Day la ba canh trong mot tam giac')

else writeln('Day khong la ba canh trong mot tam giac');

readln;

end.

Program Bai1;

Uses crt;

Var a,b,c:integer;

Begin

CLRSCR;

Write('a='); Readln(a);

Write('b='); Readln(b);

Write('c='); Readln(c);

If (a*a=b*b+c*c) then Write('a,b,c la cac canh cua 1 tam giac vuong')

else('a,b,c khong phai la cac canh cua 1 tam giac vuong');

Readln

END.

program kiem_tra;

uses crt;

var a,b,c:integer;

begin

write('nhập số a');readln(a);

write('nhập số b');readln(b);

write('nhập số c');readln(c);

if(a*a=b*b+c*c)or(b*b=c*c+a*a)or(c*c=b*b+a*a)then writeln('đây là tam giác vuông') else writeln('đây là tam giác thường');

readln;

end.

#include <iostream>
using namespace std;
int main()
{
    int a,b,c,kt;
    cout<<"Nhap a=";
    cin>>a;
    cout<<"Nhap b=";
    cin>>b;
    cout<<"Nhap c=";
    cin>>c;
    if ((a>0) and (b>0) and (c>0) and (a+b>c) and (a+c>b) and (b+c>a))
    {
        kt=0;
        if (a*a==b*b+c*c) kt=1;
        if (b*b==a*a+c*c) kt=1;
        if (c*c==a*a+b*b) kt=1;
        if ((a==b) and ((a<c) or (a>c)) and ((b<c) or (b>c))) kt=2;
        if ((b==c) and ((b<a) or (b>a)) and ((c<a) or (c>a))) kt=2;
        if ((c==a) and ((c<b) or (c>b)) and ((a<b) or (a>b))) kt=2;
        if ((a==c) and (b==c)) kt=3;
        if (kt==2) cout<<"Day la tam giac can";

else cout<<"Day khong la tam giac can";
    }
    else cout<<"Day khong la ba canh trong mot tam giac";
    return 0;
}

a = float(input("Nhap a : "))
b = float(input("Nhap b : "))
c = float(input("Nhap c : "))
if a+b>c and a+c>b and b+c>a:
    if a==b or a==c or b==c:
        if a==c==b:
            print("Day la ba canh cua tam giac deu")
        else:
            print("Day la ba canh cua tam giac can")
    elif (a**2)+(b**2)==c**2 or (a**2)+(c**2)==b**2 or (c**2)+(b**2)==a**2:
        print("Day la ba canh cua tam giac vuong")
    else:
        pass
else:
    print("Day khong phai ba canh cua tam giac")