#include<stdio.h>
#include<conio.h>
#include<stdlib.h> 

int main()
{
char ch;
float voltage , current , resistance , result;
printf("Ohms law calculator.\n");
printf("Please choose from following calculcations.\n");
printf("1. choose 1 to calculate the voltage.\n");
printf("2. choose 2 to calculate the current.\n");
printf("3. choose 3 to calculate the resistance.\n");
printf("Anything else to quit.\n");

scanf("%c",&ch);
switch(ch)
{
case '1' :
printf("please enter the current in amps.\n");
scanf("%f",&current);
printf("Now enter the resistance in ohms.\n");
scanf("%f",&resistance);
result = current * resistance;
printf("The voltage is %0.3f volts.\n",result);
break;

case '2' :
printf("please enter the voltage in volts.\n");
scanf("%f",&voltage);
printf("Now enter the resistance in ohms.\n");
scanf("%f",&resistance);
result = voltage / resistance;
printf("The current is %0.3f amps.\n",result);
break;

case '3' :
printf("please enter the voltage in volts.\n");
scanf("%f",&voltage);
printf("Now enter the current in amps.\n");
scanf("%f",&current);
result = voltage / current;
printf("The resistance is %0.3f ohms.\n",result);
break;
default :
exit(0);
break;

}
return 0;
}

void mainMenu(void);

mainMenu();

/* add your content to the mainMenu function */
void mainMenu(void) {
   int choice;
   

   do {
      gotoxy(2,1);  //or use SetConsoleCursorPosition() in Windows API
      printf("\t\t\t    Welcome to the Main Menu\n\n");
      printf("\t1) Series Circuits \n\t2. Parallel Circuits \n\t");
      printf"\n3) Quit\n\n\t    Enter Your Selection [1-3]: ");
      scanf("%d", &choice);
    
      switch(choice) {
         case 1: seriesMenu(); break;
         case 2: parallelMenu(); break;
         case 3: break;
      }
  }while(choice != 3);
}