#include <stdio.
h>
#include <math.h>
void showmenu();
double add(double a, double b);
double subtract(double a, double b);
double multiply(double a, double b);
double divide(double a, double b);
double power(double base, double exponent);
double squareRoot(double a);
double sine(double angle);
double cosine(double angle);
double tangent(double angle);
int main() {
int choice;
double num1, num2;
// Display the menu at the start
showmenu();
do {
printf("Enter your choice: ");
scanf("%d", &choice);
if (choice >= 1 && choice <= 5) {
printf("Enter your first number: ");
scanf("%lf", &num1);
printf("Enter second number: ");
scanf("%lf", &num2);
} else if (choice == 6) {
printf("Enter number: ");
scanf("%lf", &num1);
} else if (choice >= 7 && choice <= 9) {
printf("Enter angle in degrees: ");
scanf("%lf", &num1);
} else if (choice == 10) {
printf("Exiting...\n");
return 0;
} else {
printf("Invalid choice!\n");
continue; // Skip to next iteration for invalid choice
}
switch (choice) {
case 1:
printf("Result: %.2lf\n", add(num1, num2));
break;
case 2:
printf("Result: %.2lf\n", subtract(num1, num2));
break;
case 3:
printf("Result: %.2lf\n", multiply(num1, num2));
break;
case 4:
while (num2 == 0) {
printf("Error: Division by zero. Please enter a non-zero second
number: ");
scanf("%lf", &num2);
}
printf("Result: %.2lf\n", divide(num1, num2));
break;
case 5:
printf("Result: %.2lf\n", power(num1, num2));
break;
case 6:
printf("Result: %.2lf\n", squareRoot(num1));
break;
case 7:
case 8:
case 9: {
printf("Enter angle in degrees: ");
while (scanf("%lf", &num1) != 1) {
printf("Invalid input. Please enter a numeric value: ");
while (getchar() != '\n'); // Clear the input buffer
}
if (choice == 7) {
printf("Result: %.2lf\n", sine(num1 * M_PI / 180));
} else if (choice == 8) {
printf("Result: %.2lf\n", cosine(num1 * M_PI / 180));
} else if (choice == 9) {
printf("Result: %.2lf\n", tangent(num1 * M_PI / 180));
}
break;
}
}
} while (choice != 10);
return 0;
}
void showmenu() {
printf("\n--- Scientific Calculator ---\n");
printf("1. Addition\n");
printf("2. Subtraction\n");
printf("3. Multiplication\n");
printf("4. Division\n");
printf("5. Power\n");
printf("6. Square Root\n");
printf("7. Sine\n");
printf("8. Cosine\n");
printf("9. Tangent\n");
printf("10. Exit\n");
}
double add(double a, double b) { return a + b; }
double subtract(double a, double b) { return a - b; }
double multiply(double a, double b) { return a * b; }
double divide(double a, double b) { return a / b; }
double power(double base, double exponent) { return pow(base, exponent); }
double squareRoot(double a) { return sqrt(a); }
double sine(double angle) { return sin(angle); }
double cosine(double angle) { return cos(angle); }
double tangent(double angle) { return tan(angle); }
