char and const char help

[4ET0pfjN]

Hi, I am building simple program that takes three inputs as sides of a triangle
to determine the triangle type (equilateral, isosceles, scalene).

When I compile, I get the error message:

invalid conversion from 'char' to 'const char*'
initializing argument 1 of 'long int atol(const char*)

#include <iostream>

using namespace std;

int main()
{
	char side1[10], side2[10], side3[10];//USE strlen(c-string) VS length() for string object
	int iSide1 = atol(side1[0]);//we need to convert the c-string to int (non-zero returned) b/c user can enter eg: 32#2 or @33 or 3.3
	//	b/c no functions to manipulate numeric values
	int iSide2 = atol(side2[0]);//=>int side2
	int iSide3 = atol(side3[0]);
	
	
	cout << "Welcome, this program will read in three positive integers and "
		<< "determine the triangle type"<<endl;
	
	cout << "Enter side 1:";
	cin >> side1;
	cout << "Enter side 2:";
	cin >> side2;
	cout << "Enter side 3:";
	cin >> side3;
	
	if ( iSide1 == 0 || iSide2 == 0  || iSide3 == 0 )//NB: If I want to test specifically if is decimal or has alphabets and/or symbols, I need
	//	to parse each input
		cout <<"Please enter only integers!"<<endl;
	else// if they are integers 
	{	
		if ( iSide1 < 1 || iSide2 < 1 || iSide3 < 1 )
			cout <<"Please enter integers > 0!"<<endl;
		else 
		{
			if ( iSide1 == iSide2 && iSide2 == iSide3 && iSide3 == iSide1 )
				cout <<"Equilateral triangle"<<endl;
			else if ( ( iSide1 == iSide2 && iSide1 != iSide3 && iSide2 != iSide3 ) ||
						( iSide2 == iSide3 && iSide1 != iSide2 && iSide1 != iSide3 ) ||
						( iSide1 == iSide3 && iSide1 != iSide2 && iSide2 != iSide3 )
					)
				cout <<"Isosceles triangle"<<endl;
			else if ( iSide1 != iSide2 && iSide2 != iSide3 && iSide1 != iSide3 )
				cout <<"Scalene triangle"<<endl;
		}
	}
	
	cout << "Thanks for using Triangle (c)"<<endl;
	
	return 0;
}

Any help appreciated!

[subith86]

error at line 8, 10, 11

this is the prototype of atol

long int atol ( const char * str );

and what you are passing as argument is a character.
Inorder to pass the entire string, do this

atol(side1);

side1[0] is just a character and not a string.

[Ivan Sidarau]

Why are you entering information (cin >> side1;) _after_ atol ?

[bluecoder]

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


int _tmain(int argc, _TCHAR* argv[])
{

	char side1[10], side2[10], side3[10];//USE strlen(c-string) VS length() for string object
	int iSide1 = 0, iSide2 = 0 , iSide3  = 0;
	
	
	
	cout << "Welcome, this program will read in three positive integers and "
		<< "determine the triangle type"<<endl;
	
	
	cout << "Enter side 1:";
	cin >> side1;
	cout << "Enter side 2:";
	cin >> side2;
	cout << "Enter side 3:";
	cin >> side3;

	 iSide1 = atol(side1);//we need to convert the c-string to int (non-zero returned) b/c user can enter eg: 32#2 or @33 or 3.3
	//	b/c no functions to manipulate numeric values
	 iSide2 = atol(side2);//=>int side2
	 iSide3 = atol(side3);
	
	if ( iSide1 == 0 || iSide2 == 0  || iSide3 == 0 )//NB: If I want to test specifically if is decimal or has alphabets and/or symbols, I need	
		cout <<"Please enter integers!"<<endl;
	else// if they are integers 	{	
		if ( iSide1 < 1 || iSide2 < 1 || iSide3 < 1 )
			cout <<"Please enter integers > 0!"<<endl;
		else 
		{
			if ( iSide1 == iSide2 && iSide2 == iSide3 && iSide3 == iSide1 )
				cout <<"Equilateral triangle"<<endl;
			else if ( ( iSide1 == iSide2 && iSide1 != iSide3 && iSide2 != iSide3 ) ||
						( iSide2 == iSide3 && iSide1 != iSide2 && iSide1 != iSide3 ) ||
						( iSide1 == iSide3 && iSide1 != iSide2 && iSide2 != iSide3 )
					)
				cout <<"Isosceles triangle"<<endl;
			else if ( iSide1 != iSide2 && iSide2 != iSide3 && iSide1 != iSide3 )
				cout <<"Scalene triangle"<<endl;
		}
	}
	
	cout << "Thanks for using Triangle (c)"<<endl;
	
	
	return 0;
}

[4ET0pfjN]

I'm using atoi bc I know that it returns 0 if a string contains something like: "abc30", I guess I could use string manipulation to check each character to ensure is numeric via isdigit.