Logic issue with program

[lintlicker1001]

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

//prototypes for all separate functions
int chooseFunc(int);
int chooseMethod(int);
int numRect(int);
int numTrap(int, int);
int startPoint(int);
int endPoint(int);
double rectAlg(int);
int func1(double);
int func2(double);
int func3(double);
int func4(double);
int func5(double);
double funcSum(double);
//calls all the functions
int main(){
   int choose, choose2, start, end, rect, trap; 
   double answer1, answer2, answer3, answer4, answer5, x, n, rectSum, functSum;
   choose = chooseFunc(choose);
   choose2 = chooseMethod(choose2);
   rect = numRect(rect);
   trap = numTrap(trap, choose2);
   start = startPoint(start);
   end = endPoint(end);
   functSum = funcSum(n);
   rectSum = rectAlg(choose2);
   
   	return 0;
}


//asks user which function they want to use
int chooseFunc(int choose){
  cout<<"Choose a function (1,2,3,4, or 5): "<<endl;
  cin>>choose;
  return choose;
}
//asks the user which method they want to use
int chooseMethod(int choose2){
   cout<<"Would you like to calculate the area using the rectangle, trapezoid, or both? (1,2, or 3): "<<endl;
   cin>>choose2;
   return choose2;
}
//asks for the number of rectangles
int numRect(int rect){
   int choose2;
   if((choose2 == 1) || (choose2 == 3)){
      cout<<"How many rectangles would you like? "<<endl;
      cin>>rect;
      return rect;
   }
}
//asks for the number of trapezoids
int numTrap(int trap, int choose2){
   if((choose2 == 2) || (choose2 == 3))
      cout<<"How many trapezoids would you like? "<<endl;
      cin>>trap;
      return trap;
   }   
//asks the user for the starting point
int startPoint(int start){
   cout<<"Please select an integer starting point, a = "<<endl;
   cin>>start;
   return start;
}
//asks the user for the ending point
int endPoint(int end){
   cout<<"Please select an integer ending point, b = "<<endl;
   cin>>end;
   return end;
}

int func1(double x){
   int choose;
   int answer1;
   if(choose == 1){
   answer1 = (2*(pow(x,5)))+ pow(x,3)-10*x+2;}
   //return answer1;
}
int func2(double x){
   int choose;
   int answer2;
   if(choose == 2){
   answer2 = (6*(pow(x,2)))-x+10;}
   //return answer2;
}
int func3(double x){
   int choose;
   int answer3;
   if(choose == 3){
   answer3 = (5*x + 3);}
   //return answer3;
}
int func4(double x){
   int choose;
   int answer4;
   if(choose == 4){
   answer4 = (2*(pow(x,3)))+120;}
   //return answer4;
}
int func5(double x){
   int choose;
   int answer5;
   if(choose == 5){
   answer5 = (2*pow(x,2));}
}
double funcSum(double n){
   	int sum = 0;
	int choose;
	cin >> choose;
	if (choose == 1)
	   sum += func1(n);
	else if (choose == 2)
	   sum += func2(n);
	else if (choose == 3)
	   sum += func3(n);
	else if (choose == 4)
	   sum += func4(n);
	else if (choose == 5)
	   sum += func5(n);
	
}
double rectAlg(int choose2){
   int start;
   int end;
   int rect;
   double n;
   if (choose2 == 1 || choose2 == 3){
   	double increment = (endPoint(end) - startPoint(start))/numRect(rect);
   	double area = 0;
   	double total_area = 0;
   	for (int i = 1; i <= rect; i++)
   	{
   	area = i*increment * funcSum(n);
	total_area += area;
  	}
	cout << "The total area of all the rectangles for the function is:  " << total_area <<endl;}
}

It seems that my program will ask the user for the number of rectangles and trapezoids but will fail to compute the area under the curve from the user input. Therefore, I believe I have a logical error somewhere or I'm forgetting to call something somewhere.

Can someone help me find the point(s) where this is happening? Thanks!

[MikeyBoy]

Inside your rectAlg() function, you haven't initialised start, end or rect.

I'm surprised your compiler didn't warn you about that.