#include<iostream>
#include<cstdlib>
using namespace std;
double function1(double a);
double function2(double a, double b);
double function3(double a, double b, double c);
int main()
{
double a,b,c;
double result;
metka: cout<<"vvedite kolichestvo chisel (ot 1 do 3)kotoriye vi xotite vvesti:";
int m;
cin>>m;
cout<<endl<<endl;
switch (m)
{
case 1:
cout<<"vvedite chislo:";
cin>>a;
cout<<endl;
result=function1(a);
break;
case 2:
cout<<"vvedite 1-e chislo:";
cin>>a;
cout<<endl;
cout<<"vvedite 2-e chislo:";
cout<<endl;
result=function2(a,b);
break;
case 3:
cout<<"vvedite 1-e chislo:";
cin>>a;
cout<<endl;
cout<<"vvedite 2-e chislo";
cin>>b;
cout<<endl;
cout<<"vvedite 3-e chislo:";
cin>>c;
cout<<endl;
result=function3(a,b,c);
break;
default:
cout<<"\nvi vveli nepravilnoye chislo\n\n";
goto metka;
}
return 0;
}
double function(double a)
{ return a;}
double function(double a, double b)
{
return (a*a+b*b);
}
double function3(double a, double b, double c)
{
return (a*a*a+b*b*b+c*c*c);
}
#include <iostream>
using namespace std;
double fn(const double);
double fn(const double, const double);
double fn(const double, const double, const double);
double real(const char*);
int main() {
double a, b, c;
double result;
while (true) {
cout << "Quantity: ";
int n;
cin >> n;
switch (n) {
case 3: c = real("c: ");
case 2: b = real("b: ");
case 1: a = real("a: "); break;
default: return 0;
}
switch (n) {
case 1: result = fn(a); break;
case 2: result = fn(a, b); break;
case 3: result = fn(a, b, c);
}
cout << "Result: " << result << "\n\n";
}
}
double fn(const double a) {
return a;
}
double fn(const double a, const double b) {
return a * a + b * b;
}
double fn(const double a, const double b, const double c) {
return a * a * a + b * b * b + c * c * c;
}
double real(const char* msg) {
cout << msg;
double value;
cin >> value;
cin.ignore(cin.rdbuf()->in_avail());
return value;
}
Где у тебя function1 и function2? Их нет, поэтому ошибка. Точнее, они есть, но по-другому называются.
C++ в данном случае позволяет использовать одно имя для всех трёх функций.
