Let's say I have a code like this:

#include <stdio.h>
int main(void) {
    double x = 1.555;
    printf("3 decimal: %.3lf \n",x);
    printf("2 decimal: %.2lf \n",x);
    printf("1 decimal: %.1lf \n",x);
    return 0;
}

The expected output would be:

3 decimal: 1.555
2 decimal: 1.56
1 decimal: 1.6 

But instead I get:

3 decimal: 1.555
2 decimal: 1.55
1 decimal: 1.6 

Which seems wrong because it didn't round the second 5 to a 6, but it rounded the first 5 to a 6. Why is this happening?

I want to round a double to one decimal point. I tried using round() but it doesn’t work the way I need it. I want to round it so 45.892 is 45.9. How would I do this?

I have a question when it comes to rounding in C. Does it round up or down at .5? If it does round up, then does that mean that the smallest value of k in the code below can only be 1?

 int main()
{
    int k = 13;
    int i;
    for (i = 0; i < 8; i++) {
        printf("%d", (k%2));
        k >>= 1;
    }
    printf("%n");
}