Array cyclic displacement K-bit

from the programming Zhu Ji Nanxiong, the array is treated as a vector x=ab, so the array becomes BA when the loop is moved right. Considering from the angle of the vector(a-1b-1) -1=ba 

/* Do not use temporary variable Exchange A[begin] and A[end] Two memory unit contents */ Void stringreverse (char a[], int  Begin, int end) {     for (;  begin < end; begin++,  end--) {         a[begin] ^= a[end];         a[end] ^= a[begin];         a[begin] ^= a[end];     } } Void looprightshift (char a[], int n, int k) {      k %= n;          stringreverse (a, 0, n-k-1);  /* first to A[0 ... N-k-1] This (n-k) character in reverse order */     stringreverse (a, n-k, n-1);  /* again to a[n-k...n-1] This k-character is reversed */     stringreverse (a, 0, n-1);    /* ends with the entire string in reverse order */ }

Array loop shift K-bit