Solving maximal sub-array problem by divide-and-conquer method

/*     The problem is solving the maximum subarray problem      The complexity of the common method is n^2     now try to give a less than n ^2 algorithm      Of course there must be negative numbers in the array, otherwise there is no meaning      the use of divide-and-conquer strategy in this example */#include <stdio.h># include<stdlib.h>//defines the return structure of the body typedef struct result{    int left; // Left index     int right; //right index     int sum; //Max and}*res;// Solves the largest subarray containing intermediate values, with a complexity of Nres findmaxcrossingsubarray (Int *a,int left,int mid,int right) {     res r=malloc (sizeof (Struct result));     int leftsum =* (A+mid);    int sum=0;    int i;     Int maxleftindex=mid;    for (i=mid;i>=left;i--)  {         sum+=* (a+i);         if (Sum>leftSum)  {             leftsum=sum;             maxLeftIndex=i;        }     }    int rightsum=* (a+mid+1);    sum=0;     int j;    int maxrightindex=mid+1;    for (j=mid+1;j <=right;j++)  {        sum+=* (A+j);         if (sum>rightsum)  {             rightsum=sum;            maxrightindex =j;        }    }    r-> Left=maxleftindex;    r->right=maxrightindex;    r->sum= (LeftSum +rightsum);    return r;} Next, we use the divide-and-conquer method to find the maximum subarray of an array, with the assumption that there are negative elements, otherwise meaningless res findmaxsubarray (Int *a,int low,int high) {     if (High==low)  {        res res= malloc (sizeof (struct result));        res->left=low;         res->right=high;         res->sum=* (a+low);         return res;    }     else {        int mid= (Low+high)/2;         res resleft=findmaxsubarray (A,low,mid);         res resright=findmaxsubarray (A,mid+1,high);         res rescross=findmaxcrossingsubarray (A,low,mid,high);       &nbSp; if (resleft->sum)  >=  (resright->sum)  &&  (resleft->sum)   >=  (rescross->sum))             return  resleft;        else if (resright->sum)  >=  (resleft->sum)  &&  (resright->sum)  >=  (rescross->sum))              return resRight;         else              return rescross;    }}//Main test Program Void main () {    int a[8]={ 5,-1,4,5,-2,3,-1,2};    res res=findmaxsubarray (a,0,7);     printf ("%d\n", Res->sum);}

Solving maximal sub-array problem by divide-and-conquer method