C++ 数组元素操作

数组元素的移除

• 核心思路：创建一个新的内存空间存储移除后的数组，再将原数组delete释放，再将指针指向新数组。

cout << "----------------------------- 数组元素的移除 -------------------------" << endl;
//cout << deleteArrByIndex(0, arr11) << endl;// 示例数组
int * pArr = new int[5] {1,3,5,7,9};
int * pNewArr = new int[4];
int deleteIndex = 2;    // 移除下标为2的元素
int len = 5;
for (int i = 0; i < len; ++i) {if(i == 2) {continue;}if(i <= 2) {pNewArr[i] = pArr[i];}else {pNewArr[i - 1] = pArr[i];}
}
delete[] pArr;  // 回收老数组的空间pArr = pNewArr; // 将老数组的指针指向新数组的内存空间
// 打印删除后的数组
for (int i = 0; i < 4; ++i) {cout << pArr[i] << endl;
}

数组元素的插入

        int * pArr2 = new int[]{1,2,3,4,5};  // 1  , 3下标插入 0int * pInsert = new int[7];int offset =  0;for (int i = 0; i < 5; ++i) {if(i == 1 || i == 3) {pInsert[i + offset] = 0;offset ++;}pInsert[i + offset] = pArr2[i];}delete[] pArr2;pArr2 = pInsert;for (int i = 0; i < 7; ++i) {cout << "pArr2[" << i << "] = " << pArr2[i] << endl;}