这个求最大子序列的程序为什么不能输出正确答案？该怎么解决

这个求最大子序列的程序为什么不能输出正确答案？？

C/C++ code

#include <stdio.h>#include <conio.h>#define N 6main(){    int i;    int a[N]={-2,11,-4,13,-5,-2};    printf("the old older is:\n");        for(i=0;i<N;i++)            printf("%d  ",a[i]);                printf("\n");                     i=MaxSubsequenceSum4(a,N);                 printf("the max is %d\n",i);                printf("\n");        getch();}intMaxSubsequenceSum4(const int a[],int n)     {    int ThisSum,MaxSum,j;     ThisSum=MaxSum=0;      for(j=0;j<n;j++)      {        ThisSum+=a[j];         if(ThisSum>MaxSum)            MaxSum=ThisSum;         else if(ThisSum<0)            MaxSum=0;      }     return MaxSum;}