#include <iostream>
#include <stdio.h>
#include <conio.h>
#include <math.h>
#include <cmath>
#include <iomanip>

using namespace std;

float f(float x);

int main()
{
float x1,x2,xr,error,tol;
int i=1;
cout<<"========METODE BAGI DUA======="<<endl<<endl;;
cout<<"f(x) =2^x-5x+2"<<endl;
//User menginput nilai x1 dan x2
cout<<"Masukkan batas bawah persamaan(x1): "; cin>>x1;
cout<<"Masukkan batas atas persamaan (x2): ";cin>>x2;
if (f(x1)*f(x2)>0){
do{
    cout<<"Masukkan lagi x1 dan x2 sehingga f(x1)*f(x2)<0"<<endl;
    cout<<"Masukkan batas bawah persamaan(x1): "; cin>>x1;
    cout<<"Masukkan batas atas persamaan (x2): ";cin>>x2;
    }
while (f(x1)*f(x2)>0);
}

cout<<"Masukkan nilai batas error: ";cin>>tol;

{
cout<<setw(5)<<"i"<<setw(15)<<"x1"<<setw(20)<<"x2"<<setw(20)<<"xr"<<setw(20)<<"f(x1)";
cout<<setw(20)<<"f(x2)"<<setw(20)<<"f(xr)"<<setw(20)<<"error"<<endl;
do
{
xr=(x1+x2)/2;
error= abs(x2-x1);
cout<<setw(5)<<i<<setw(15)<<x1<<setw(20)<<x2<<setw(20)<<xr<<setw(20)<<f(x1)<<setw(20);
cout<<f(x2)<<setw(20)<<f(xr)<<setw(20)<<error<<endl;
if(f(x1)*f(xr)<0)
{x2=xr;}
else
{x1=xr;
}
i++;
}
while( (error > tol) && (i < 40));
cout<<"Approx. root = "<<xr<<endl;
cout<<"Banyaknya iterasi : "<<i-1;

}
getch();
return 0;
}
float f(float x)
{
return (pow(2,x)-(5*x)+2);
}

C++ Online Compiler

Write, Run & Share C++ code online using OneCompiler's C++ online compiler for free. It's one of the robust, feature-rich online compilers for C++ language, running on the latest version 17. Getting started with the OneCompiler's C++ compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as C++ and start coding!

Read inputs from stdin

OneCompiler's C++ online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

#include <iostream>
#include <string>
using namespace std;

int main() 
{
    string name;
    cout << "Enter name:";
    getline (cin, name);
    cout << "Hello " << name;
    return 0;
}

About C++

C++ is a widely used middle-level programming language.

  • Supports different platforms like Windows, various Linux flavours, MacOS etc
  • C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
  • Case-sensitive
  • C++ is a compiler based language
  • C++ supports structured programming language
  • C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
  • Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}