0 failures but does not complile. Does anyone know what is happening?

#include<stdio.h>
float choice;
float result;
float num1, num2;
int get_choice();
int main()
{
{
	float num1, num2;
	int choice;
	float result;

	do
	{
	printf("Welcome to Colleen Gonzales's Handy Calculator");
	printf("1. Addition\n");
	printf("2. Subtract\n");
	printf("3. Multipilcation\n");
	printf("4. Division\n");
	printf("5. Exit\n");

	printf("\n\nPlease pick an operation.\n");
	scanf("%f", &choice);
	}
	while(  (choice = 1,2,3, 4 , 5) );

	printf("Please choose two numbers seperated by a space:");
	scanf("%f %f", &num1, &num2);

	return 0;
}
		
{	
	float num1, num2, result;
	int choice;

while( (choice=get_choice()) !=5)
{
switch (choice)
			{
case 1 : result = num1 + num2;
break;
case 2 : result = num1-num2;
break;
case 3 : result = num1 * num2;
break;
case 4 : result = num1/num2;
break;
case 5 : printf("Goodbye");
						break;
			default  :printf("Please respond with 1, 2, 3, 4, or 5\n");
						break; /*end of switch*/
			}
	}


printf("The result of %f and %f is %.2f\n", &num1, & num2, &result);

	return 0;
}
}

#include<stdio.h>

float choice;
float result;
float num1, num2;
int get_choice();

int main()
{
    {
        float num1, num2;
        int choice;
        float result;

        do
        {
            printf("Welcome to Colleen Gonzales's Handy Calculator");
            printf("1. Addition\n");
            printf("2. Subtract\n");
            printf("3. Multipilcation\n");
            printf("4. Division\n");
            printf("5. Exit\n");

            printf("\n\nPlease pick an operation.\n");
            scanf("%f", &choice);
        }
        while( (choice = 1,2,3, 4 , 5) );

        printf("Please choose two numbers seperated by a space:");
        scanf("%f %f", &num1, &num2);

        return 0;
    }

    {	
        float num1, num2, result;
        int choice;

        while( (choice=get_choice()) !=5)
        {
            switch (choice)
            {
                case 1 : result = num1 + num2;
                        break;
                case 2 : result = num1-num2;
                        break;
                case 3 : result = num1 * num2;
                        break;
                case 4 : result = num1/num2;
                        break;
                case 5 : printf("Goodbye");
                        break;
                default:  printf("Please respond with 1, 2, 3, 4, or 5\n");
                        break; /*end of switch*/
            }
        }


        printf("The result of %f and %f is %.2f\n", &num1, & num2, &result);

        return 0;
        }
    }

    while(choice == 1 || choice == 2 || choice == 3 ||
                     choice ==  4  || choice ==  5) );

#include<stdio.h>
//==>rasbv:Removed unwanted variables.
//int choice;
//float result;
//float num1, num2;

//rasbv: note I chaged the return to be float as the result will be in float
//rasbv: add to argument list using by value here
float get_choice(float num1, float num2, int choice);

//==>rasbv:Note that your "copy paste"  have errors on brackets
int main()
{
	int choice;
	float result;
	float num1, num2;
	char buff[256];

	do
	{
		printf("Welcome to Colleen Gonzales's Handy Calculator\n\n");
		printf("\n\nPlease pick an operation.\n");
		printf("1. Addition\n");
		printf("2. Subtract\n");
		printf("3. Multipilcation\n");
		printf("4. Division\n");
		printf("5. Exit\n");

		printf("\n\nYour choice is:");
		scanf("%d", &choice);
		flushall();

		if((choice<=4) && (choice>=1)) 
		{
			//rasbv: Ask for the 2 numbers inside the loop
			printf("Please choose two numbers seperated by a space:\n");
			fgets(buff, 256, stdin); //<-- rasbv:use fgets to read the whole line and later sscanf to get the 2 numbers
			if(sscanf(buff, "%f %f", &num1, &num2)==2) 
			{
				result=get_choice(num1, num2, choice); //<-rasbv: call the function
			}
			else
			{
				printf("Error in sscanf\n\n");
			}
		}
			
	}
	while( (choice<=4)&&(choice>=1));//<-rasbv: change the condition to be between 1 to 4

	printf("\n\nThank you for using.\nPlease come again :)\n Tata!!\n");

	return 0;
}

float get_choice(float num1, float num2, int choice)
{	
	//==>rasbv:Removed unwanted variables.
	float result;

	switch (choice)
	{
		case 1 : result = num1 + num2;
		break;
		case 2 : result = num1-num2;
		break;
		case 3 : result = num1 * num2;
		break;
		case 4 : result = num1/num2;
		break;
		case 5 : printf("Goodbye");
		break;
		default: printf("Please respond with 1, 2, 3, 4, or 5\n");
		break; /*end of switch*/
	}
	printf("The result of %.4f and %.4f is %.2f\n", num1, num2, result);//<--rasbv: no & here
	return result;

}

#include<stdio.h>

void do_the_computation(float num1, float num2, int choice) {	
  float result;
  char*operator;
  switch (choice) {
           case 1 : result = num1 + num2;operator = "plus";
    break; case 2 : result = num1-num2;  operator = "minus";
    break; case 3 : result = num1 * num2;operator = "times";
    break; case 4 : result = num1 / num2;operator = "divided by";
    break; case 5 : fputs("Goodbye",stdout); /* never happens because you prescreened choice */
    break; default: puts("Please respond with 1, 2, 3, 4, or 5"); /* never happens because you prescreened choice */
    break; /*end of switch*/
  }
  printf("The result of %.4f %s %.4f is %.2f\n", num1, operator, num2, result);
}

int main() {
  int choice;
  float num1, num2;
  char buff[256];
  puts("Welcome to Colleen Gonzales's Handy Calculator\n");
  do {
    puts("\n\nPlease pick an operation.");
    puts("1. Addition");
    puts("2. Subtract");
    puts("3. Multiplication");
    puts("4. Division");
    puts("5. Exit");
    fputs("\n\nYour choice is:",stdout);
    scanf("%d", &choice);
    while('\n' != getchar())
      ;
    if (5 == choice)
      choice = 0;
    else if ((choice < 1) || (4 < choice))
      choice = 1;
    else {
      puts("Please choose two numbers seperated by a space:");
      fgets(buff, 256, stdin);
      if(2 == sscanf(buff, "%f %f", &num1, &num2))
	do_the_computation(num1, num2, choice);
      else
	puts("Error in sscanf\n");
    }
  } while(choice);
  puts("\n\nThank you for using.\nPlease come again :)\n Tata!!");
  return 0;
}

while(choice>0&&choice<6)