Question

如何在不更改格式的情况下删除所有空格，以及这样做的最佳选择是什么，如果这样做，我将使用System.out.printf（）;或其他一些指令。请使用Java而不是C ++进行响应。我真的很感谢任何能提供帮助的人，并非常感谢他们为我解决自己的问题。

public class WorldPopulation{
    //main string
    public static void main(String[] args) {
             //prints title 
            System.out.println(" This is a estimate of world population growth within 300 year time span. ");
            //prints number value
            System.out.println("                       Numbers are in millions");
            //number of rows and columns
            final int ROWS = 6;
            final int COLUMNS = 7;

            //population numbers array
            int [] [] populations =
                {
                        {106, 107, 111, 133, 221, 767, 1766},
                        {502, 635, 809, 947, 1402, 3634, 5268},
                        {2, 2, 2, 6, 13, 30, 46},
                        {163, 203, 276, 408, 547, 729, 628},
                        {2, 7, 26, 82, 172, 307, 392},
                        {16, 24, 3, 74, 167, 511, 809}
                };
            //continents array
            String[] continents =
                {
                        "Africa",
                        "Asia",
                        "Australia",
                        "Europe",
                        "North America",
                        "South America"
                };
            //prints the years used in the estimation       
            System.out.println("                Year 1750 1800 1850 1900 1950 2000 2050");

            //print population data
            for (int i = 0; i < ROWS; i++)
    {          
             //print i'th row       
            System.out.printf("%20s", continents[i]);
            //prints the columns and the rows
            for (int j = 0; j < COLUMNS; j++) {

                System.out.printf("%5d", populations [i] [j]);
            }
                System.out.println(); //start new line at end of row
        }



            //print column totals
            System.out.printf("%20s","World total");
            //prints the total estimated population in the years used
            for (int  j = 0; j < COLUMNS; j++)
            {
                int total = 0;
                for (int i = 0; i < ROWS; i++) {
                    total = total + populations[i][j];
                }
                //format of the printed totals  
                System.out.printf("%5d", total);

            }
            //starts new line after each row
            System.out.println();
        }
        //end of class and program.
    }

Answer 1

您可以执行以下操作：

System.out.format("%15s%s", "", "Test");

您有一个长度为15的字符串，后跟一个未定义的字符串。因为第一个要格式化的字符串是一个空字符串，所以将打印15个空格。

Answer 2

您需要用以下行替换您的行：

System.out.printf("%16s%s\n"," ","Year 1750 1800 1850 1900 1950 2000 2050");

如您所见，我输入了两个格式参数：

%16s for " "
%s for "Year 1750 1800 1850 1900 1950 2000 2050"

除了format参数之外，我还用\n换行了。

在第11行中，我如何做到这一点，所以我不需要使用太多空间

2 个答案: