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我試圖循環二維數組,但由於某些原因的聲明:爲什麼這個代碼在c中失敗?
var = matrix[i + 1][j] // Fails for i = 1 and j = 0
但
next = i + 1; var = matrix[next][j] // Works, why???..
我認爲它應該工作,因爲如果我等於一個和我加1是2 ,並且我知道價值並不是空的,至少在我的情況下,有一點要提到的是我正在測試以下輸入:> 4 4 1,這意味着一個4x4的矩陣和一個旋轉,所以我確定矩陣[2] [0]不是空的事實,我可以打印它並訪問它和所有。
這裏是整個代碼:
#include <stdio.h>
#include <stdlib.h>
void rotateMatrix(int** matrix, int top, int right, int left, int bottom)
{
//int rows = right;
//int columns = bottom;
int rowScan = 0;
int columnScan = 0;
int high = 0;
int low = 0;
int test = matrix[2][0];
for (int i = 0; rowScan != 1;)
{
for (int j = 0; columnScan != 1;)
{
//int next = i + 1;
high = matrix[i + 1][j]; //FAILS HERE WHEN
matrix[i + 1][j] = low != 0 ? low : matrix[i][j];
i++;
if (i >= bottom)
{
bottom--;
break;
}
if ((i + 1) < bottom)
{
low = matrix[i + 1][j];
matrix[i + 1] = high;
}
if ((i + 1) == bottom)
{
columnScan = 1;
rowScan = 1;
}
}
}
}
int main()
{
//-- Declaring variables
int rows, columns, rotations;
//-- Initializing variables
rows = 0;
columns = 0;
rotations = 0;
//-- Scanning parameters and adding them to the stdin buffer
scanf("%d %d %d", &rows, &columns, &rotations);
//-- Initializing 2D array to save the Matrix values allocating space in memory
int **matrix = (int**)malloc(rows * sizeof(int*));
//-- Initializing each allocated pointer to each column size
for (int i = 0; i < rows;i++)
matrix[i] = malloc(columns * sizeof(int));
//-- Scanning Matrix values and saving them into stdin buffer
for (int i = 0; i < rows; i++)
for (int j = 0; j < columns; j++)
matrix[i][j] = rand() % 10;
// scanf("%d", &matrix[i][j]);
//-- Rotating R times
while ((rotations--) != 0)
rotateMatrix(matrix, 0, columns, 0, rows);
for (int i = 0; i < rows; i++)
{
for (int j = 0; j < columns; j++)
{
printf("%d", matrix[i][j]);
}
printf("\n");
}
getchar();
getchar();
return 0;
}
請解釋什麼是「失敗」? –
內存訪問衝突 – user3044096
@ user3044096使用調試器進入代碼,找到導致崩潰的行,跟蹤變量中的值並檢查是否有可疑內容。 –