multiplying two numbers returns -1821066134 in c code example

Example 1: multiplication of two numbers in c

int num1,num2;
printf("%d",num1*num2);

Example 2: C multiply

// Program to multiply 2 numbers from user inputs

#include <stdio.h>
int main() {
    double a, b, product;
    printf("Enter two numbers: ");
    scanf("%lf %lf", &a, &b);  
 
    // Calculating product
    product = a * b;

    // Result up to 2 decimal point is displayed using %.2lf
    printf("Product = %.2lf", product);
    
    return 0;
}