C++ errors ,unsure of problem

[sharkcoder]

I am new to C++ and have a code that I need to fix. I am using C++ Visual Studio Express 2010. I am getting multiple errors and I am unsure of how to fix them Can someone help me fix this or show me how to do this correctly using Visual Studio express.

I am trying to write a program that accepts as input the bill for a meal at a restaurant, calculates the tax, the tip, and the total and then displays the amounts.
Calculate the tax using a tax rate of 7% (use a value of 0.07).
Calculate the tip using 18% (use a value of 0.18).
Your program should do the following:
1. Prompt the user for the amount of the meal.
2. Calculate the tax.
3. Calculate the tip.
4. Calculate the total.
5. Display the following values:
The amount on the bill for the meal
The amount you should pay for tax
The amount for the tip
The total amount you should pay (meal + tax + tip).
HINT: Use the data type double for these variables.

Below is the code I currently have

 #include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;
 
int main()
{
   double cost;
   double tax;
   double tip;
   double total;
 
   cout <<"please enter the cost of your meal: ";
   cin >> cost;
 
   tax = cost * 0.07;
   tip = cost * 0.18;
   total = cost + tax + tip;
 
   cout << setprecision(2) << fixed;
   cout <<"\n\nThe cost of your meal is: " << cost << "\n";
   cout <<"\n\nThe tax amount is: " << tax << "\n";
   cout <<"\n\nThe tip amount is: " << tip << "\n";
   cout <<"\n\nThe total cost is: " << total << "\n";
 
 
   return 0;
}


int _tmain(int argc, _TCHAR* argv[])
{
	return 0;
}

The error says : 1>------ Build started: Project: proj, Configuration: Debug Win32 ------
1> proj.cpp
1>LINK : warning LNK4067: ambiguous entry point; selected 'mainCRTStartup'
1>LINK : fatal error LNK1123: failure during conversion to COFF: file invalid or corrupt
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

[helios]

Delete the _tmain() function.

[wildblue]

You can only have one main function. The compiler error about ambiguous entry point is likely referring to you having both int main and int _tmain.