Hex Magic square C language

The method may be a bit stupid, take the first outer ring (1-12), and then the Middle (13-18) of the sorting method, so that the first pruning as far as possible to cut off three sums, and then remove four sum.

But with arrays only, checking for repetition seems like a difficult thing to do, and the 12 results are actually one, 2 (mirror) *6 (angle)

Original code, lhy1024

#include <stdio.h> #include <time.h> #define SUM 38int count=0;int Check (int a[],int flag), int arrange (int a[] , int ordinal), void magic_printf (int a[]), int main () {int a[20]= {0};d ouble start,finish; Start=clock ();//Timing part arrange (A, 1); Finish=clock ();p rintf ("%f seconds\n", (Finish-start)/clocks_per_sec); return 0;} int arrange (int a[],int ordinal) {int i,j;if (ordinal==20) {count++;magic_printf (a);//last one to print}else {int b[20]= { 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19};for (i=1; i<=ordinal-1; i++) {b[a[i]]=0;//used numbers turn the switch to zero}for (i= 1; i<=19; i++) {if (b[i]!=0) {a[ordinal]=i;if (check (a,ordinal) ==1)//If eligible, recursively next arrange (a,ordinal+1);}}} int check (int a[],int flag) {if (flag==3| | flag==5| | flag==7| | flag==9| | flag==11) {if (a[flag-2]+a[flag-1]+a[flag]!=sum) return 0;} if (flag==14) {if (a[12]+a[13]+a[14]+a[4]!=sum) return 0;} if (flag==15) {if (a[2]+a[14]+a[15]+a[6]!=sum) return 0;} if (flag==16) {if (a[4]+a[15]+a[16]+a[8]!=sum) return 0;} if (flag==17) {if (a[10]+a[17]+a[16]+a[6]!=sum) return 0;} If(flag==18) {if (a[8]+a[17]+a[18]+a[12]!=sum) return 0;if (A[2]+a[13]+a[18]+a[10]!=sum) return 0;} if (flag==19) {if (a[1]+a[13]+a[19]+a[16]+a[7]!=sum) return 0;if (a[3]+a[14]+a[19]+a[17]+a[9]!=sum) return 0;if (a[11]+ A[18]+a[19]+a[15]+a[5]!=sum) return 0;} return 1;} void magic_printf (int a[]) {printf ("Case:%d\n", Count);p rintf ("%2d%2d%2d\n", a[1],a[2],a[3]);p rintf ("%2d%2d%2   D%2d\n ", A[12],a[13],a[14],a[4]);p rintf ("%2d%2d%2d%2d%2d\n ", a[11],a[18],a[19],a[15],a[5]);p rintf ("%2d%2d%2d %2d\n ", a[10],a[17],a[16],a[6]);p rintf ("%2d%2d%2d\n ", a[9],a[8],a[7]);p rintf (" \ n ");}

Hex Magic square C language