What does this Error mean?

int colum_num; int get total (int[][colum_num]); double average(int); int get totalRow (int[l[colum_num],int) int get_totalColum (int[][colum_num],int); double get_avg(int) int highest_inRow(int[1[colum_num], int); int lowest_inRow (int [colum_num],int); int main() int ch, value,i,j; int num [ rows ] [ colums]= {10, 20 , 30, 40); cout>ch switch (ch) case 1: cout