Version abc51001

2 files changed, 33 insertions, 0 deletions

diff --git a/src/misc/extra/extra.h b/src/misc/extra/extra.h
index 904d550f..5305ae31 100644
--- a/src/misc/extra/extra.h
+++ b/src/misc/extra/extra.h
@@ -261,6 +261,8 @@ extern int         Extra_Power3( int Num );
 /* the number of combinations of k elements out of n */
 extern int         Extra_NumCombinations( int k, int n  );
 extern int *       Extra_DeriveRadixCode( int Number, int Radix, int nDigits );
+/* counts the number of 1s in the bitstring */
+extern int         Extra_CountOnes( unsigned char * pBytes, int nBytes );
 /* the factorial of number */
 extern int         Extra_Factorial( int n );
 /* the permutation of the given number of elements */
diff --git a/src/misc/extra/extraUtilMisc.c b/src/misc/extra/extraUtilMisc.c
index 6d771990..75e91cbc 100644
--- a/src/misc/extra/extraUtilMisc.c
+++ b/src/misc/extra/extraUtilMisc.c
@@ -209,6 +209,37 @@ int * Extra_DeriveRadixCode( int Number, int Radix, int nDigits )
     return Code;
 }
 
+/**Function*************************************************************
+
+  Synopsis    [Counts the number of ones in the bitstring.]
+
+  Description []
+
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Extra_CountOnes( unsigned char * pBytes, int nBytes )
+{
+    static int bit_count[256] = {
+      0,1,1,2,1,2,2,3,1,2,2,3,2,3,3,4,1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
+      1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
+      1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
+      2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
+      1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
+      2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
+      2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
+      3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,4,5,5,6,5,6,6,7,5,6,6,7,6,7,7,8
+    };
+
+    int i, Counter;
+    Counter = 0;
+    for ( i = 0; i < nBytes; i++ )
+        Counter += bit_count[ *(pBytes+i) ];
+    return Counter;
+}
+
 /**Function********************************************************************
 
   Synopsis    [Computes the factorial.]