leetCode 53: Maximum Subarray

题目如下：

Find the contiguous subarray within an array (containing at least one number) which has the largest sum.
For example, given the array [−2,1,−3,4,−1,2,1,−5,4],
the contiguous subarray [4,−1,2,1] has the largest sum = 6.

 

原型：最大连续和问题

 

《算法竞赛入门经典》模版：

S[0] = 0;
for (i = 1; i <= n; i++)  S[i] = S[i-1] + A[i];
for (i = 1; i <= n; i++) 
     for (j = i; j <= n; j++) 
          best = max(best, S[j] - S[i-1]);

 

 

本题代码：

int maxSubArray(int* nums, int numsSize) {
    int *S;
    S = (int*)malloc((numsSize+5) * sizeof(int) );
    int i,j;
    int best = nums[0];
    S[0] = 0;
    
    for (i=1; i<=numsSize; i++) {
        S[i] = S[i-1] + nums[i-1];
    }
    for (i=1; i<=numsSize; i++) {
        for (j=i; j<=numsSize; j++) {
            best = best > (S[j]-S[i-1]) ? best : (S[j]-S[i-1]);
        }
    }
    free(S);
    return best;
}