C++二维数组在函数模版里的应用

Question

C++里我们定义一个n行n列的二维数组data，定义函数模板calcu()用来计算data每一行从1号元素到n-1号元素的总和，并将其保存到该行的0号元素中，函数返回变化后主对角线的和，再用函数模版print()输出data，如何实现呢？

Answer 1

稍等，写个程序给你

#include <iostream>

using namespace std;

template<typename T, int n>
T calcu(T (&data)[n][n]) {
    T sum = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 1; j < n - 1; j++) {
            data[i][0] += data[i][j];
        }
        sum += data[i][i];
    }
    return sum;
}

template<typename T, int n>
void print(T (&data)[n][n]) {
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            cout << data[i][j] << "\t";
        }
        cout << endl;
    }
}

int main() {
    int n = 4;
    int data[n][n] = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10, 11, 12}, {13, 14, 15, 16}};
    int sum = calcu(data);
    cout << "对角线的和是: " << sum << endl;
    print(data);
    return 0;
}