Binary Search help

[passingBy]

Hello, I am having trouble compiling this code that finds a number in a given array using a binary search. I was able to get most of it with help from my book
but for some reason I keep getting syntax errors on line 57. "expected primary expression for "else" ". I keep looking for my error but I cannot find it. Any tips and advice would be greatly appreciated

#include <iostream>            // needed for Cin and Cout
#include <string>              // needed for the String class
#include <math.h>              // math functions
#include <stdlib.h>  
#include <iomanip>     
using namespace std;


int binarySearch(const int [], int, int);
const int size = 20;


int main()
{
    // variable list
    int searchNumber;                 // the number you are searching for in the array
    int intArray [20] = {2, 4, 5, 8, 9, 12, 16, 18, 19, 23, 33, 36, 38, 38, 45, 48, 59, 66, 79, 666};
    int results; 
    
    
    cout << "please enter a number to search for: ";
    cin >> searchNumber;
    
    results = binarySearch(intArray, size, searchNumber);
    
    if (results == -1)
    {
                cout << " That number does not exist in the array \n";
                

    else 
    {
         cout << " That number is found at element " << results;
         cout << " in the array. \n";
    }
    return 0;

}
    
    /***************************
    *     print array
    ***************************/
    for (int x=0; x<20; x++)
    {
      if(x%5 ==0)
      {
        cout << "\n";
      }
      cout << setw(5) << intArray[x];
    }
    cout << "\n\n";
    
    
    
    int binarySearch( int intArray[], int size, int value);
    {
    int value;
    int first = 0;                   //First Array element 
    int last = size -1;              // Last Array element
    int middle;                     //  Mid-point of search
    int position = -1;              //postion of search
    bool found = false;            // flag
    
    while (!found && first <= last)
    {
          middle = (first + last) /2;
          if (intArray[middle] == value)
          { 
                found = true; 
                position = middle; 
          }
          else if (intArray[middle] > value)
             last = middle -1;
          else 
             first = middle +1;
    }
    return position;
}
                               
    
   
    system("pause");
    return 0;
}

[rezy3312]

{}

[wildblue]

31:5: error: expected '}' before 'else'

There's an opening { at line 27, but no matching close } on line 30 before the else.

43:5: error: expected unqualified-id before 'for' 
43:19: error: 'x' does not name a type 
43:25: error: 'x' does not name a type 
51:5: error: 'cout' does not name a type 

Lines 40 - 51 - is this supposed to be in the main function, or will this be a separate print function? Line 36-38 end the main function, so this code is just sitting out in global space right now. There's also what seems to be the end of main at line 82-84.

56:5: error: expected unqualified-id before '{' token

Remove the ; at the end of line 55.

In function 'int binarySearch(int*, int, int)': 60:9: error: declaration of 'int value' shadows a parameter

In line 55, you have an int value as one of the parameters. Line 57 then declares a new int value. If you want to use the value sent into the function as value, remove line 57.

[passingBy]

hey wildblue, thanks for the response.

The matching close for line 27 would be on line 38 no?
I removed line 55 and now it is telling me that value is undelcared, and im still getting an error before "else".

Edit :
Okay I got rid of the error with "else" and i rearranged some things, but I am still getting
a " [Linker error] undefined reference to `binarySearch(int const*, int, int)' "

#include <iostream>            // needed for Cin and Cout
#include <string>              // needed for the String class
#include <math.h>              // math functions
#include <stdlib.h>  
#include <iomanip>     
using namespace std;


/*************************************
*     function prototype
*************************************/
int binarySearch(const int [], int, int);
const int size = 20;

int main()
{
    // variable list
    int searchNumber;                 // the number you are searching for in the array
    int intArray [size] = {2, 4, 5, 8, 9, 12, 16, 18, 19, 23, 33, 36, 38, 38, 45, 48, 59, 66, 79, 666};
    int results; 
     
    cout << "please enter a number to search for: ";
    cin >> searchNumber;
    
    // search for number 
    results = binarySearch(intArray, size, searchNumber);
    
    if (results == -1)
    cout << " That number does not exist in the array \n";
    else 
    { 
         cout << " That number is found at element " << results;
         cout << " in the array. \n";
         }    
    
    
    /***************************
    *     print your array
    ***************************/
    for (int x=0; x<20; x++)
    {
      if(x%5 ==0)
      {
        cout << "\n";
      }
      cout << setw(5) << intArray[x];
    }
    cout << "\n\n";  
                                                   
    return 0;
}
int binarySearch( int intArray[], int size, int value)
    {
    int first = 0;                   //First Array element 
    int last = size -1;              // Last Array element
    int middle;                     //  Mid-point of search
    int position = -1;              //postion of search
    bool found = false;            // flag
    
    while (!found && first <= last)
    {
          middle = (first + last) /2;
          if (intArray[middle] == value)
          { 
                found = true; 
                position = middle; 
          }
          else if (intArray[middle] > value)
             last = middle -1;
          else 
             first = middle +1;
    }
    return position;
}

[wildblue]

The matching close for line 27 would be on line 38 no?

No - the compiler is expecting a closing } for the if before the else.

Line 55, just remove the ; at the end of the line, and add const to match your prototype of the function.

int binarySearch( const int intArray[], int size, int value); // remove ; at end and add const to match prototype at line 9
    {
    int value;  // remove redeclaration of value
    int first = 0;                   //First Array element 
    int last = size -1;              // Last Array element
    int middle;                     //  Mid-point of search
    int position = -1;              //postion of search
    bool found = false;            // flag
    
    while (!found && first <= last)
    {
          middle = (first + last) /2;
          if (intArray[middle] == value)
          { 
                found = true; 
                position = middle; 
          }
          else if (intArray[middle] > value)
             last = middle -1;
          else 
             first = middle +1;
    }
    return position;
}

[passingBy]

I found the problem I just had to put "const" in front of int intArray[] in line 52. Thanks again

[wildblue]

[Linker error] undefined reference to `binarySearch(int const*, int, int)' "

That linker error is because the function prototype and definition don't match on the const keyword.

int binarySearch(const int [], int, int);
int binarySearch( int intArray[], int size, int value)