I am trying to make a simple program that finds the sum of 1 + 1/2 + … + 1/n. However, I have stumbled upon an interesting issue: this for loop works with int but not with double.

double num, result = 1;
  
double main(){

    printf("Input a number: ");
    scanf("%f", &num);

    for (double i = 1; i < num; i++)
    {
        result += 1/i;
    }

    printf("Result: %f", result);    

    return 0;
}

After replacing every int and %d with double and %f, the loop gets skipped and I cannot figure out why. Does anyone have an explanation for this?