Introduction to algorithms problem 2-4 inversions

Change it on the basis of merge sort.

1  Public classInversions {2     3      Public Static intInversions (int[] A,intPintR)4     {   5         6         if(p<R)7         {8             intQ = (int) Math.floor ((p+r)/2 );9             intleft =inversions (a,p,q);Ten             intright = inversions (a,q+1, R); One             intc =combine (a,p,q,r); A             returnLeft + right +C; -         } -         return0; the  -     } -      Public Static intCombineint[] A,intPintQintR) -     { +         inttotal_inversions = 0; -          +         intN1 = q-p+1; A         intN2 = RQ; at         int[] L =New int[N1]; -         int[] R =New int[N2]; -          for(inti=0; i<n1; i++) -L[i] = a[p+i]; -          for(inti=0; i<n2;i++) -R[i]=a[q+i+1]; in          -         intI=0; to         intJ=0; +         intCounter =p; -          while(I<l.length && j<r.length) the         { *             if(l[i]<=R[j]) $             {Panax Notoginsenga[counter]=L[i]; -i++; the             } +             Else A             { thea[counter]=R[j]; +J + +; -Total_inversions + = (q (p+i) +1); $             } $counter++; -         } -         if(i==l.length) the         { -              for(intk=j;k<r.length;k++)Wuyia[counter++] =R[k]; the         } -         Else Wu         { -              for(intk=i;k<l.length;k++) Abouta[counter++] =L[k]; $         } -         returntotal_inversions; -     } -      Public Static voidMain (string[] args) { A         intA[] = {2,3,8,6,1,7,9,1}; +         intNum_of_inversions = Inversions (a,0,a.length-1); the System.out.println (num_of_inversions); -     } $}

Introduction to algorithms problem 2-4 inversions