C语言二维数组周边元素平均值计算函数

#include<stdio.h> #include<conio.h> #include<stdlib.h> #define N 5 double fun (int w[][N]) { int i, j; double sum = 0.0; for (i = 0; i < N; i++) { for (j = 0; j < N; j++) { // 判断是否为周边元素 if (i == 0 || j == 0 || i == N - 1 || j == N - 1) { sum += w[i][j]; } } } return sum / ((N - 2) * 2 + (N - 2) * 2 - 4); }

void main() { FILE wf; int a[N][N]={0,1,2,7,9,1,9,7,4,5,2,3,8,3,1,4,5,6,8,2,5,9,1,4,1}; int i, j; double s; system("CLS"); printf("The array\n "); for (i=0; i<N; i++) { for (j=0;j<N;j++) {printf("%4d ",a[i][j]);} printf("\n "); } s=fun(a); printf("THE result\n "); printf("The average is : %.3lf\n ",s); // wf=fopen("out.dat","w"); fprintf (wf,"%lf",s); fclose(wf); // }