我正在为 C++ 编写一个程序，该程序接受用户输入，第一行包含 1-9 之间的 n 个整数，该整数告知以下数据的网格大小。然后是具有 n 列和行的网格。接下来是一个整数 m ，详细说明数组上将发生多少个操作，其中每个操作都在下一行的 m 行中进行。我认为我在提取数据并告诉循环停止并再次重复方面遇到困难。我的代码如下：
#include <iostream>
#include <string>
#include <array>
using namespace std;
// GLOBAL CONSTANTS
const size_t MAX = 9; /// Maximum dimension of a grid
// PROTOTYPES HERE
void swap_rows(int grid[][MAX], size_t a, size_t b, size_t size);
void swap_columns(int grid[][MAX], size_t a, size_t b, size_t size);
void increment_grid(int grid[][MAX], size_t size);
void decrement_grid(int grid[][MAX], size_t size);
void transpose_grid(int grid[][MAX], size_t size);
int main() {
// Variable declaration
int case_num = 1;
int grid[MAX][MAX];
int n; // size of array taken from int
int m;
string op;
// ** input *****************************************************
do {
cin >> n;
cin.clear();
if (n < 0 && n > 9){
cin.fail();
}
// ** process ***************************************************
for (size_t i = 0; i < MAX; i++){
for (size_t j = 0; j < MAX; j++) {
cin >> grid[i][j]; // take in data to make grid
}
}
cin.clear();
cin >> m; // input num of operations
// using for loop to apply operation to grid and print
for (int i = 0; i < m; i++) { //iterate through list m times
cin >> op;
if (op == "row") {
int a;
int b;
cin >> a >> b;
swap_rows(grid, a, b, n); // for zero-based inputs
} else if (op == "col"){
int a;
int b;
cin >> a >> b;
swap_columns(grid, a, b, n);
} else if (op == "inc"){
increment_grid(grid, n);
} else if (op == "dec"){
decrement_grid(grid, n);
} else if (op == "transpose"){
transpose_grid(grid, n);
}
}
// ** Output ****************************************************
cout << "Case #" << case_num << endl;
case_num++;
for (size_t i = 0; i < MAX; i++){ // print new array
for (size_t j = 0; j < MAX; j++){
cout << grid[i][j];
cout << '\n';
}
}
cout << endl;
} while (cin.good()); // continue loop
return 0;
}
/// @brief the function swaps two rows in a given grid.
///
/// @param [in,out] grid - the grid in which rows are to be swapped
/// @param a - the first row to be swapped (zero-based index)
/// @param b - the second row to be swapped (zero-based index)
/// @param size - The size of the grid (number of rows/ columns).
/// @return none
void swap_rows(int grid[][MAX], size_t a, size_t b, size_t size) {
int temp;
// go through every column
for (size_t col = 0; col < size; col++) {
// swap [a] [col] with [b][col] use temp variable to store a variable
temp = grid[a][col];
grid[a][col] = grid[b][col];
grid[b][col] = temp; // declare temp variable to [b]
}
}
/// @brief the function swaps two columns in a given grid.
///
/// @param [in,out] grid - the grid in which columns are to be swapped
/// @param a - the first column to be swapped (zero-based index)
/// @param b - the second column to be swapped (zero-based index)
/// @param size - The size of the grid (number of rows/ columns).
/// @return none
void swap_columns(int grid[][MAX], size_t a, size_t b, size_t size) {
int temp;
// go through every row
for (size_t row = 0; row < size; row++) {
// swap [row] [a] with [row][b] use temp variable to store a variable
temp = grid[row][a];
// declare b variable to [a] declare temp variable to [b]
grid[row][a] = grid[row][b];
grid[row][b] = temp;
// increase i and repeat loop until array is finished
}
}
/// @brief the function increments each element in the grid by 1, wrapping
/// around to 0 at 10
///
/// @param [in,out] grid - the grid to be incremented
/// @param size - The size of the grid (numbers of rows/columns
/// @return none
void increment_grid(int grid[][MAX], size_t size) {
// go through every row in every column
for (size_t i = 0; i < size; i++) {
for (size_t j = 0; j < size; j++) {
grid[i][j]++; //increment the element
if (grid[i][j] > 9) {
grid[i][j] = 0;
}
}
}
}
/// @brief the function decrements each element in the grid by 1, wrapping
/// around to 9 at -1
///
/// @param [in,out] grid - the grid to be decremented
/// @param size - The size of the grid (numbers of rows/columns
/// @return none
void decrement_grid(int grid[][MAX], size_t size) {
// go through every row in every column
for (size_t i = 0; i < size; i++) {
for (size_t j = 0; j < size; j++) {
grid[i][j]--; //decrement the element
if (grid[i][j] < 0) {
grid[i][j] = 9;
}
}
}
}
/// @brief the function transposes the given grid
///
/// @param [in,out] grid - the grid to be incremented
/// @param size - The size of the grid (numbers of rows/columns
/// @return none
void transpose_grid(int grid[][MAX], size_t size) {
int temp;
// loop should start at row 2, go through every row
for (size_t i = 1; i < size; i++){
for (size_t j = 1; j < i; j++){
temp = grid[i][j];
grid[j][i] = grid[i][j];
grid[i][j] = temp;
}
}
}
我尝试更改循环变量以及 while 语句将保存的内容。我还尝试调试错误，因为数组难以选择正确的数据。
示例输入如下所示：
4
1234
5678
1234
5678
1
transpose
3
000
111
000
2
row 1 2
inc
0
我怎样才能更好地修复我的代码以产生正确的结果并正常运行
阅读主要内容第一行后的一些评论：
if (n < 0 && n > 9)
我猜你的意思是|| ：这个说法不可能
您的示例输入无效：大小 4 表示预期有 4 x 4 = 16 个输入的网格，您太早输入“转置”了...
// ** process ***************************************************
for (size_t i = 0; i < MAX; i++){
for (size_t j = 0; j < MAX; j++) {
cin >> grid[i][j]; // take in data to make grid
}
此外，因为您要求大小（用户输入“n”变量），但在循环中使用 MAX...
这与我的第一条评论相关：我建议你让你的程序说出它期望的输入，以便你在使用调试器之前更好地理解正在发生的事情，这将是“我怎样才能更好地修复我的问题”的进一步步骤代码”，但我认为还没有必要。
另外，正如 @mikeb 所说，“阅读关于作业的公开信：https://softwareengineering.meta.stackexchange.com/questions/6166/open-letter-to-students-with-homework-problems”
祝你好运！