#include<stdio.h>

typedef struct cell *CellPtr;
typedef struct cell {
    int contents, row, col;
    CellPtr next, down;
} Cell;

CellPtr revSparse(CellPtr matrix, int width) {
    CellPtr col, row = matrix, temp=matrix, curr = matrix, p = matrix;
    int new_row;
    for (row = matrix; row != NULL; row = row->down) {
        new_row = 1;
        while (temp != NULL) {
            if (row == matrix) {
                new_row = 0;
                curr = matrix;
                col = curr->next;
                temp = col->next;
                curr = col;
                matrix->next = NULL;
            }
            if (new_row == 1) {
                new_row = 0;
                col->down = row;
            }
            if (new_row == 0) {
                col = curr->next;
                temp = col->next;
                col->next = curr;
                curr = col;
            }
            if (curr == matrix) {
                curr->next = NULL;
            }
            if (p == matrix && temp->next == NULL) {
                p = temp;
            }
        }
        return p;
    }
}

int main() {
    Cell t1 = {6, 1, 2, NULL, NULL};
    Cell t2 = {2, 1, 5, NULL, NULL};
    Cell t3 = {8, 1, 6, NULL, NULL};
    Cell t4 = {1, 1, 7, NULL, NULL};
    Cell t5 = {44, 2, 1, NULL, NULL};
    Cell t6 = {7, 2, 2, NULL, NULL};
    Cell t7 = {7, 2, 5, NULL, NULL};
    Cell t8 = {11, 2, 6, NULL, NULL};

    CellPtr p;
    p = &t1;
    t1.next = &t2;
    t2.next = &t3;
    t3.next = &t4;
    t1.down = &t5;
    t5.next = &t6;
    t6.next = &t7;
    t7.next = &t8;


    revSparse(p, 20);


    return 0;
}