#include <iostream>
using namespace std;
float chuvi(int a, int b, int c) {
    return a + b + c;
}
float dientich(int a, int b, int c) {
    float p = chuvi(a, b, c) / 2.0;
    return sqrt(p*(p - a)*(p - b)*(p - c));
}
int main(){
    float a, b, c;
    cout << "Nhap canh a: ";
    cin >> a;
    cout << "Nhap canh b: ";
    cin >> b;
    cout << "Nhap canh c: ";
    cin >> c;
    if (a >= b + c || b >= a + c || c >= a + b)
        cout << "Ba canh vua nhap khong phai la canh cua tam giac";
    else {
        cout << "Chu vi  "<<chuvi(a,b,c)<<endl;
        cout << "Dien tich  " << dientich(a, b, c)<<endl;
    }
    system("pause");
    return 0;
}
 

Mã:#include<iostream> #include<math.h>

int main()

{

int a,b,c;

float p,dientich,chuvi;

cout<<"nhap a"<<endl;

cin>>a;

cout<<"nhap b"<<endl;

cin>>b;

cout<<"nhap c"<<endl;

cin>>c;

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

if((a+b>c)&&(a+c>b)&&(b+c>a)&&(a>0)&&(b>0)&&(c>0))

{

cout<<"dien tich tan giac= "<<sqrt(p*(p-a)*(p-b)*(p-c))<<"\n";

cout<<"chu vi tam giac= "<<a+b+c<<"\n";

}

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