为什么我写的这个表格排序会出现乱码，还有如何让中文和数字对齐，我明明每段字都给两个空格但是仍旧无法对其

#include <iostream>
using namespace std;
int main()
{
    float a[6][5],t;
    int i, j, m;
    float sum = 0;
    for (i = 0; i < 5; i++)
        for (j = 0; j < 4; j++)
            cin >> a[i][j];

    for (i = 0; i < 5; i++)
    {
        sum = 0.0;
        for (j = 1; j < 4; j++)
            sum =sum+ a[i][j];
        a[i][4] = sum;
    }
    for(j=1;j<5;j++)
    {
        sum = 0.0;
        for (i = 0; i < 5; i++)
            sum =sum+ a[i][j];
        a[5][j] = sum / 5;
    }
for(i=0;i<4;i++)
    {
        m = i;
        for (j = i + 1; j < 5; j++)
            if (a[m][4] < a[j][4])m=j;
        if (m != i) for(j=0;j<5;j++)
        { t = a[i][j];
        a[i][j] = a[m][j];
        a[m][j] = t;
        }
    }
    cout << "学号" << "  " << "数学" << "  " << "外语" << "  " << "语文 "<< "  " <<"总成绩" << endl;
                for (i = 0; i < 6; i++)
                {
                    for (j = 0; j < 5; j++)
                    {
                        cout << a[i][j] << "   ";
                        if (i == 5 && j == 0)cout << "平均成绩" << "  ";
                    }
                    cout << endl;
                }
                return 0;

            }

37行改成cout << "学号" << "\t" << "数学" << "\t" << "外语" << "\t" << "语文 "<< "\t" <<"总成绩" << endl;
42行改成cout << a[i][j] << "\t";
至于为什么乱码，你试试吧47行删了