1: /*
2: @@
3: Author: Justinzhang
4: Email: uestczhangchao@gmail.com
5: time: 2012-9-1 21:40:13
6: desc: find the max sum of sub arrys; This file was created at an earlier time;
7: At that time, i didn't read the programming perls, in that book, there is a detailed
8: discussion about this problem. The fastest algrithm can solve it in O(n) time;
9: So if have spare time, read more of it.
10: @@
11: */
12:
13: #include <iostream>
14: #include <vector>
15: #include <algorithm>
16: #include <iomanip>
17: using namespace std;
18:
19: template<class type>
20: type getMax(type param1, type param2)
21: { 22: return (param1>param2 ? param1 : param2);
23: }
24:
25: template<class type> type find_max_sum_of_subarray(vector<type> vec)
26: { 27: type maxSum = 0;
28: type curMaxSum = 0;
29: for(unsigned int i=0; i < vec.size(); i++)
30: { 31: curMaxSum += vec[i];
32: curMaxSum = getMax(0, curMaxSum);
33: maxSum = getMax(maxSum, curMaxSum);
34: }
35: return maxSum;
36: }
37:
38:
39: int main()
40: { 41: int array[] = {-2, 5, 3,-6, 44, -8, 16}; 42: /* /!\ note that: to use array to initialize vector, the second parameter is the length of array,
43: not the length of array minus 1.
44: */
45: vector<int> vec(array,array+(sizeof array / sizeof(int)));
46: cout << "find_max_sum_of_subArray: " << find_max_sum_of_subarray<int>(vec) << endl;
47: return 0;
48: }