#include<stdio.h>
#include<conio.h>
#include<math.h>
#include<stdlib.h>
#define PI 3.14159265
#define KEY "Enter the calculator Operation you want to do:"
void addition();
void subtraction();
void multiplication();
void division();
void modulus();
void power();
int factorial();
void calculator_operations();
void root();
void exponent();
void logten();
void sine();
void cosine();
void tangent();
void secant();
void cosec();
int main()
{
    system("color 4E");
    printf("\t\t\t\t===========================================================\n");
    printf("\t\t\t\t::=======================================================::\n");
    printf("\t\t\t\t::             PROJECT NAME:SIMPLE CULCULATOR            ::\n");
    printf("\t\t\t\t::                  Istaiq Ahmed-ID:19105008             ::\n");
    printf("\t\t\t\t::                  Farhan Labib-ID:19105025             ::\n");
    printf("\t\t\t\t::=======================================================::\n");
    printf("\t\t\t\t===========================================================\n");
    printf("press any key to clear screen:");
    char ch;
    fflush(stdin);
    scanf("%c",&ch);
    if(ch=='c')
    {
        system("cls");
    }
    system("COLOR 70");
    int X=1;
    char Calc_oprn;
    calculator_operations();

    while(X)
    {
        printf("\n");
        printf("%s ", KEY);
        Calc_oprn=getche();

        switch(Calc_oprn)
        {
        case '+':
            addition();
            break;

        case '-':
            subtraction();
            break;

        case '*':
            multiplication();
            break;

        case '/':
            division();
            break;

        case '?':
            modulus();
            break;

        case '!':
            factorial();
            break;

        case '^':
            power();
            break;
        case 'H':
        case 'h':
            calculator_operations();
            break;
        case 'r':
            root();
            break;
        case 'e':
            exponent();
            break;
        case 'l':
            logten();
            break;
        case 's':
            sine();
            break;
        case 'k':
            cosine();
            break;
        case 't':
            tangent();
            break;
        case 'n':
            cotangent();
            break;
        case 'a':
            secant();
            break;
        case 'b':
            cosec();
            break;

        case 'Q':
        case 'q':
            exit(0);
            break;
        case 'c':
        case 'C':
            system("cls");
            calculator_operations();
            break;

        default :
            system("cls");

            printf("\n**********You have entered unavailable option");
            printf("***********\n");
            printf("\n*****Please Enter any one of below available ");
            printf("options****\n");
            calculator_operations();
        }
    }
}

//Function Definitions

void calculator_operations()
{

    printf("\n             Welcome to C calculator \n\n");

    printf("***** Press 'Q' or 'q' to quit ");
    printf("the program ********\n");
    printf("*** Press 'H' or 'h' to display ");
    printf("below options *****\n\n");
    printf("Enter 'C' or 'c' to clear the screen and");
    printf(" display available option \n\n");

    printf("Enter + symbol for Addition \n");
    printf("Enter - symbol for Subtraction \n");
    printf("Enter * symbol for Multiplication \n");
    printf("Enter / symbol for Division \n");
    printf("Enter ? symbol for Modulus\n");
    printf("Enter ^ symbol for Power \n");
    printf("Enter ! symbol for Factorial \n");
    printf("Enter r symbol for square root \n");
    printf("Enter e symbol for exponent \n");
    printf("Enter l symbol for logten \n");
    printf("Enter s symbol for sine \n");
    printf("Enter k symbol for cosine \n");
    printf("Enter t symbol for tangent \n");
    printf("Enter n symbol for cotangent \n");
    printf("Enter a symbol for secant \n");
    printf("Enter b symbol for cosec \n");

}

void addition()
{
    int n, total=0, k=0, number;
    printf("\nEnter the number of elements you want to add:");
    scanf("%d",&n);
    printf("Please enter %d numbers one by one: \n",n);
    while(k<n)
    {
        scanf("%d",&number);
        total=total+number;
        k=k+1;
    }
    printf("Sum of %d numbers = %d \n",n,total);
}

void subtraction()
{
    int a, b, c = 0;
    printf("\nPlease enter first number  : ");
    scanf("%d", &a);
    printf("Please enter second number : ");
    scanf("%d", &b);
    c = a - b;
    printf("\n%d - %d = %d\n", a, b, c);
}

void multiplication()
{
    int a, b, mul=0;
    printf("\nPlease enter first numb   : ");
    scanf("%d", &a);
    printf("Please enter second number: ");
    scanf("%d", &b);
    mul=a*b;
    printf("\nMultiplication of entered numbers = %d\n",mul);
}

void division()
{
    int a, b, d=0;
    printf("\nPlease enter first number  : ");
    scanf("%d", &a);
    printf("Please enter second number : ");
    scanf("%d", &b);
    d=a/b;
    printf("\nDivision of entered numbers=%d\n",d);
}

void modulus()
{
    int a, b, d=0;
    printf("\nPlease enter first number   : ");
    scanf("%d", &a);
    printf("Please enter second number  : ");
    scanf("%d", &b);
    d=a%b;
    printf("\nModulus of entered numbers = %d\n",d);
}

void power()
{
    double a,num, p;
    printf("\nEnter two numbers to find the power \n");
    printf("number: ");
    scanf("%lf",&a);

    printf("power : ");
    scanf("%lf",&num);

    p=pow(a,num);

    printf("\n%lf to the power %lf = %lf \n",a,num,p);
}

int factorial()
{
    int i,fact=1,num;

    printf("\nEnter a number to find factorial : ");
    scanf("%d",&num);

    if (num<0)
    {
        printf("\nPlease enter a positive number to");
        printf(" find factorial and try again. \n");
        printf("\nFactorial can't be found for negative");
        printf(" values. It can be only positive or 0  \n");
        return 1;
    }

    for(i=1; i<=num; i++)
        fact=fact*i;
    printf("\n");
    printf("Factorial of entered number %d is:%d\n",num,fact);
    return 0;
}
void root()
{
    double first;
    printf("\nPlease Enter Only One Value: ");
    scanf("%lf",&first);
    printf("sprt(%.1lf) = %.1lf", first,sqrt(first));
}
void exponent()
{
    float x;
    printf("\nEnter one number to find exponent: ");
    scanf("%f",&x);
    printf("%.2f",exp(x));
}
void logten()
{
    double x;
    printf("\nEnter one number to find logten: ");
    scanf("%lf",&x);
    printf("%.2lf",log10(x));
}
void sine()
{
    double x,d,val;
    printf("\nEnter one number to find sin: ");
    scanf("%lf",&x);
    if(x==90||x==180||x==0)
    {
        val = PI / 180;
        d=sin(x*val);
        printf("%.2lf",round(d));

    }
    else
    {
        val = PI / 180;
        d=sin(x*val);
        printf("%.2lf",d);
    }

}
void cosine()
{
    double x,d,val;
    printf("\nEnter one number to find cos: ");
    scanf("%lf",&x);
    val = PI / 180;
    d=cos(x*val);
    printf("%.2lf",d);
}
void tangent()
{
    double x,d,val;
    printf("\nEnter one number to find tan: ");
    scanf("%lf",&x);
    if(x==90||x==270)
    {
        printf("Math ERROR!");
    }
    else
    {
        val = PI / 180;
        d=tan(x*val);
        printf("%.2lf",d);
    }

}
void cotangent()
{
    double x,d,val;
    printf("\nEnter one number to find cot: ");
    scanf("%lf",&x);
    if(x==0||x==180||x==360)
    {
        printf("Math ERROR!");
    }
    else
    {
        val = PI / 180;
        d=tan(x*val);
        printf("%.2lf",1/d);
    }
}
void secant()
{
    double x,d,val;
    printf("\nEnter one number to find sec: ");
    scanf("%lf",&x);
    if(x==90||x==270)
    {
        printf("Math ERROR!");
    }
    else
    {
        val = PI / 180;
        d=cos(x*val);
        printf("%.2lf",1/d);
    }
}
void cosec()
{
    double x,d,val;
    printf("\nEnter one number to find cosec: ");
    scanf("%lf",&x);
    if(x==0||x==180||x==360)
    {
        printf("Math ERROR!");
    }
    else
    {
        val = PI / 180;
        d=sin(x*val);
        printf("%.2lf",1/d);
    }
}