直方图是颠倒的

Question

I want my histogram to show like this

but I get it upside down like this

This is my code.

public void printHistogram() {
    System.out.println("Print histogram");
    histogram = new boolean[4][6];
    int[] lengthTemp = numberEach(numbers);

    for (int u = 0; u < 4; u++) {
        for (int m = 0; m < 6; m++) {
            if (lengthTemp[m] >= 1) {
                histogram[u][m] = true;
                lengthTempk[m] -= 1;
            }
        }
    }

    for (int s1 = 0; s1 < 4; s1++) {
        for (int s2 = 0; s2 < 6; s2++) {
            if (histogram[s1][s2]) {
                System.out.print("*\t");
            } else {
                System.out.print(" \t");
            }
        }
        System.out.println("");
    }
}

I keep trying to reverse it but I never get it right. I found out that you just need to reverse it to the middle but I can't figure it out.

Every true in the array histogram represents a star.

Answer 1

In the first dimension of your array histogram , the first index 0 is printed first, at the top of the histogram, not the bottom.

To get your print outs to print correctly, print from the end of the first dimension s1 , not the beginning. Subtract s1 from the length of the 2D array. Change your s1 for loop to iterate backwards.

for (int s1 = 0; s1 < 4; s1++) {

to

for (int s1 = 3; s1 >= 0; s1--) {

Answer 2

reverse the reading of the array :

for (int s1 = 3; s1 >= 0; s1--) {
   ...
}