c++ 的用 new 和delete 進行二維陣列動態記憶體的建立和刪除
阿新 • • 發佈:2019-02-09
1.陣列指標 A (*ga)[n] = new A[m][n]; ... delete []ga; 2.二級指標 A** ga = new A*[m]; for(int i = 0; i < m; i++) ga[i] = new A[n]; ... for(int i = 0; i < m; i++) delete []ga[i]; delete []ga; 3.//用一維陣列來模擬 A* ga = new A[m*n]; ... delete []ga;
對應的用malloc 和free 函式進行操作的方法是: 1. int (*p)[4] = (int *[])malloc(sizeof(int) *n * m); free(p); 2. int **p; for(int i = 0; i < n; i ++) { p[i] = (int *)malloc(sizeof(int) * m); } for(int i = 0; i < n; i ++) free(p[i]); free(p); 3. int *p = (int *) malloc(sizeof(int) * n *m); free(p);