#include #include #include // shuffle array values right<=>left to center int a[10] = { [9] = 0, [0] = 1, [8] = 2, [1] = 3, [7] = 4, [2] = 5, [6] = 6, [3] = 7, [5] = 8, [4] = 9 }; int main() { printf("static Shuffle array - defined diameter 5 => size 10.:\n"); for (int i=0; i < 10; i++ ) printf("%i, ", a[i]); putc('\n',stdout); printf("Ordered static Shuffle array - alg i know:\n"); for (int i=0; i < 5; i++ ) printf("%i, %i, ", a[9-i], a[i]); putc('\n',stdout); printf("Ordered static Shuffle array - unsafe alg calc next index:\n"); { int i=9; while(1){ printf("%i, ", a[i]); if( i==4 )break; i=(i>4?9-i:8-i); } } putc('\n',stdout); printf("please input step grow for array diameter (1.. 500)"); int igrowstep; char sgrowstep[1000]={0}; scanf("%s", sgrowstep); igrowstep = atoi( sgrowstep ); if((igrowstep <= 0) || (igrowstep > 500)){ printf("incorrect input step grow for array diameter: \"%s\"", sgrowstep ); return 1; }; int inewdiam = 5+igrowstep; int inewsize = inewdiam*2; printf("dinamic Shuffle array - grow diameter from 5 to %i => new size %i.:\n", inewdiam , inewsize ); int* a2 = (int*)calloc(inewsize , sizeof(int)); if(a2!=NULL){ memcpy(a2,a,10*sizeof(int)); memmove(a2+(inewdiam+igrowstep), a2+5, 5*sizeof(int)); memset(a2+5, 0, 2*igrowstep*sizeof(int)); printf("growed dinamic Shuffle array - diameter %i => size %i.:\n", inewdiam , inewsize ); for (int i=0; i < inewsize ; i++ ) printf("%i, ", *(a2+i)); { putc('\n',stdout); int v=0; for (int i=0; i < inewdiam ; i++ ){ *(a2+(inewsize - i)-1) = v++; *(a2+i) = v++; }; } printf("inited dinamic Shuffle array - diameter %i => size %i.:\n", inewdiam , inewsize ); for (int i=0; i < inewsize ; i++ ) printf("%i, ", *(a2+i)); putc('\n',stdout); printf("Ordered dinamic Shuffle array - unsafe alg calc next index:\n"); { int i=inewsize-1; while(1){ printf("%i, ", *(a2+i)); if( i==inewdiam-1 )break; i=(i>(inewdiam -1)?(inewsize -1)-i:(inewsize -2)-i); } } putc('\n',stdout); free(a2); } return 0; }

Unsafe trick of array logic - interesting