void band()
{
    fp2 = fopen( "b.txt", "r" );
    int  band[8][11];
    printf( "请选择:\n" );
    printf( "\t\t\t1--高数\n\t\t\t2--工图\n\t\t\t3--英语\n\t\t\t4--C语言\n\t\t\t5--航概\n\t\t\t6--体育\n\t\t\t7--思修\n" );
    scanf( "%d", &choice );
    for( i = 1 ; i <= 7; i++ )
        if( choice == i ){
            for( j = 1; j <= 7 ; j++ )
                for( i = 1;i <= 10; i++)
                band[j][i] = 0;
                for( i = 1; i <= 20; i++ )
                    for( j = 1; j <= 7; j++ ){
                        if( stu[i].cj[j] <= 10 )
                            band[j][1]++;
                        else if( stu[i].cj[j] <= 20 )
                            band[j][2]++;
                        else if( stu[i].cj[j] <= 30 )
                            band[j][3]++;
                        else if( stu[i].cj[j] <= 40 )
                            band[j][4]++;
                        else if( stu[i].cj[j] <= 50 )
                            band[j][5]++;
                        else if( stu[i].cj[j] <= 60 )
                            band[j][6]++;
                        else if( stu[i].cj[j] <= 70 )
                            band[j][7]++;
                        else if( stu[i].cj[j] <= 80 )
                            band[j][8]++;
                        else if( stu[i].cj[j] <= 90 )
                            band[j][9]++;
                        else band[j][10]++;
                    }
        }
        for( j = 1; j <= 10; j++ )
            printf( "分数段在0--%d的人数有:%d\n", 10*j, band[i][j] );

};

void band()
{
    fp2 = fopen( "b.txt", "r" );
    int  band[8][11];
    int choice;//声明
    printf( "请选择:\n" );
    printf( "\t\t\t1--高数\n\t\t\t2--工图\n\t\t\t3--英语\n\t\t\t4--C语言\n\t\t\t5--航概\n\t\t\t6--体育\n\t\t\t7--思修\n" );
    scanf( "%d", &choice );
    for( i = 1 ; i <= 7; i++ )
        if( choice == i ){
            for( j = 1; j <= 7 ; j++ )
                for( i = 1;i <= 10; i++)
                band[j][i] = 0;
                for( i = 1; i <= 20; i++ )
                    for( j = 1; j <= 7; j++ ){
                        if( stu[i].cj[j] <= 10 )
                            band[j][1]++;
                        else if( stu[i].cj[j] <= 20 )
                            band[j][2]++;
                        else if( stu[i].cj[j] <= 30 )
                            band[j][3]++;
                        else if( stu[i].cj[j] <= 40 )
                            band[j][4]++;
                        else if( stu[i].cj[j] <= 50 )
                            band[j][5]++;
                        else if( stu[i].cj[j] <= 60 )
                            band[j][6]++;
                        else if( stu[i].cj[j] <= 70 )
                            band[j][7]++;
                        else if( stu[i].cj[j] <= 80 )
                            band[j][8]++;
                        else if( stu[i].cj[j] <= 90 )
                            band[j][9]++;
                        else band[j][10]++;
                    }
        }
        for( j = 1; j <= 10; j++ )
            printf( "分数段在0--%d的人数有:%d\n", 10*j, band[i][j] );

}//这的逗号应该不要吧

你试试哦！

学习

谢谢了，这只是我的一部分程序，choice是定义了的