矩阵中间行和列的总和 · GeeksForGeeks 中文系列教程

# 矩阵中间行和列的总和 > 原文： [https://www.geeksforgeeks.org/sum-middle-row-column-matrix/](https://www.geeksforgeeks.org/sum-middle-row-column-matrix/) 给定一个奇数尺寸（3 * 3，5 * 5）的整数矩阵。那么任务是找到中间行&列元素的总和。例子： ``` Input : 2 5 7 3 7 2 5 6 9 Output : Sum of middle row = 12 Sum of middle column = 18 Input : 1 3 5 6 7 3 5 3 2 1 1 2 3 4 5 7 9 2 1 6 9 1 5 3 2 Output : Sum of middle row = 15 Sum of middle column = 18 ``` ## CPP ``` // C++ program to find sum of // middle row and column in matrix #include <iostream> using namespace std; const int MAX = 100; void middlesum(int mat[][MAX], int n) { int row_sum = 0, col_sum = 0; //loop for sum of row for (int i = 0; i < n; i++) row_sum += mat[n / 2][i]; cout << "Sum of middle row = " << row_sum<<endl; //loop for sum of column for (int i = 0; i < n; i++) col_sum += mat[i][n / 2]; cout << "Sum of middle column = " << col_sum; } // Driver function int main() { int mat[][MAX] = {{2, 5, 7}, {3, 7, 2}, {5, 6, 9}}; middlesum(mat, 3); return 0; } ``` ## Java ```java // java program to find sum of // middle row and column in matrix import java.io.*; class GFG { static int MAX = 100; static void middlesum(int mat[][], int n) { int row_sum = 0, col_sum = 0; // loop for sum of row for (int i = 0; i < n; i++) row_sum += mat[n / 2][i]; System.out.println ( "Sum of middle row = " + row_sum); // loop for sum of column for (int i = 0; i < n; i++) col_sum += mat[i][n / 2]; System.out.println ( "Sum of middle column = " + col_sum); } // Driver function public static void main (String[] args) { int mat[][] = {{2, 5, 7}, {3, 7, 2}, {5, 6, 9}}; middlesum(mat, 3); } } // This code is contributed by vt_m. ``` ## Python3 ```py # Python program to find sum of # middle row and column in matrix def middlesum(mat,n): row_sum = 0 col_sum = 0 # loop for sum of row for i in range(n): row_sum += mat[n // 2][i] print("Sum of middle row = ", row_sum) # loop for sum of column for i in range(n): col_sum += mat[i][n // 2] print("Sum of middle column = ", col_sum) # Driver code mat= [[2, 5, 7], [3, 7, 2], [5, 6, 9]] middlesum(mat, 3) # This code is contributed # by Anant Agarwal. ``` ## C# ```cs // C# program to find sum of // middle row and column in matrix using System; class GFG { //static int MAX = 100; static void middlesum(int [,]mat, int n) { int row_sum = 0, col_sum = 0; // loop for sum of row for (int i = 0; i < n; i++) row_sum += mat[n / 2, i]; Console.WriteLine ( "Sum of middle row = " + row_sum); // loop for sum of column for (int i = 0; i < n; i++) col_sum += mat[i, n / 2]; Console.WriteLine ( "Sum of middle column = " + col_sum); } // Driver function public static void Main () { int [,]mat = {{2, 5, 7}, {3, 7, 2}, {5, 6, 9}}; middlesum(mat, 3); } } // This code is contributed by vt_m. ``` ## PHP ```php <?php // PHP program to find sum of // middle row and column in matrix function middlesum( $mat, $n) { $row_sum = 0; $col_sum = 0; //loop for sum of row for ( $i = 0; $i < $n; $i++) $row_sum += $mat[$n / 2][$i]; echo "Sum of middle row = " , $row_sum,"\n"; //loop for sum of column for ( $i = 0; $i < $n; $i++) $col_sum += $mat[$i][$n / 2]; echo "Sum of middle column = " , $col_sum; } // Driver function $mat = array(array(2, 5, 7), array(3, 7, 2), array(5, 6, 9)); middlesum($mat, 3); // This code is contributed by anuj_67\. ?> ``` 输出： ``` Sum of middle row = 12 Sum of middle column = 18 ``` **时间复杂度**：`O(n)` * * * * * *