Why debugger shows problem before sorting? [closed] - c++

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I have problem with my program written in C. I want to draw int numbers to 2-size array, show it and then sort numbers in lines, and then make transposition with array, but it doesn't work. debugger show error in line with printf in function main() but i totally don't know what's wrong.
Thank for all support.
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <algorithm>//dla swapa
void draw(int **tab, int m, int n)
{
for (int i = 0; i < m; i++)
{
for (int j = 0; j < n; j++)
{
tab[m][n] = rand() % (100 + 1); //0-100
}
}
}
void sort(int **tab, int m, int n)
{
m = 0;
while (m)
{
for (int j = n - 1; j > 0; j--)
{
for (int i = 0; i < n; i++)
{
if (tab[i] > tab[i + 1])
{
std:: swap(tab[i], tab[i + 1]);
}
}
}
m++;
}
for (int i = 0; i < m; i++)
{
for (int j = 0; j < n; j++)
{
printf("|%d||[%d|\n", tab[i][j]);
}
}
}
int main()
{
int w, k;
int **tab;
printf("Lines: ");
scanf(" %d", &w);
printf("columns: ");
scanf(" %d", &k);
tab = (int**)malloc(w*sizeof(int*));
for (int i = 0; i < k; i++) {
tab[i] = (int*)malloc(k * sizeof(int));
}
printf("\nBefore sorting: \n");
for (int i = 0; i < w; i++)
{
for (int j = 0; j < k; i++)
{
printf("|%d||%d|", tab[i][j]);
}
}
// lub tab=(int*)malloc(w*k*sizeof(int));
srand(time(NULL));
draw(tab, w, k);
printf("\nSorted array:\n");
sort(tab,w,k);
}

Answer 1

The line for (int i = 0; i < k; i++) { should be for (int i = 0; i < w; ++i)
The line printf("|%d||%d|", tab[i][j]); should be printf("tab[%d][%d] = %d\n", i, j, tab[i][j]);
Your function sort() is wrong.
You should use like row, col not w, k
The following code could work:
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <algorithm>
void draw(int **tab, int row, int col) {
for (int i = 0; i < row; ++i)
for (int j = 0; j < col; ++j)
tab[i][j] = rand() % (100 + 1);
}
void sort(int **tab, int row, int col) {
int x = 0;
int y = 0;
while (x != row) {
int temp = tab[x][y];
for (int j = y + 1; j != col; ++j)
if (tab[x][j] < tab[x][y])
std::swap(tab[x][j], tab[x][y]);
for (int i = x + 1; i != row; ++i)
for (int j = 0; j != col; ++j)
if (tab[i][j] < tab[x][y])
std::swap(tab[i][j], tab[x][y]);
++y;
if (y == col) {
y = 0;
++x;
}
}
}
void output(int** tab, int row, int col) {
for (int i = 0; i < row; ++i)
for (int j = 0; j < col; ++j)
printf("tab[%d][%d] = %d\n", i, j, tab[i][j]);
}
int main() {
int row, col;
int **tab;
printf("Lines: ");
scanf(" %d", &row);
printf("columns: ");
scanf(" %d", &col);
tab = (int **)malloc(row * sizeof(int *));
for (int i = 0; i < row; ++i)
tab[i] = (int *)malloc(col * sizeof(int));
printf("\nBefore sorting: \n");
srand(time(NULL));
draw(tab, row, col);
output(tab, row, col);
printf("\nSorted array:\n");
sort(tab, row, col);
output(tab, row, col);
return 0;
}

Answer 2

The following lines (it appears twice):
printf("|%d||[%d|\n", tab[i][j]);
Wants to print two numbers but you are only giving it a single value tab[i][j] to print.
You also need to look at this code:
tab = (int**)malloc(w*sizeof(int*));
for (int i = 0; i < k; i++) {
tab[i] = (int*)malloc(k * sizeof(int));
}
Here you allocate w array elements but then use kwhen in the for loop.