最大子序列和算法

#include "stdio.h"

//算法1:

int MaxSubsequenceSum1(const int A[], int N)

{

int ThisSum, MaxSum, i, j, k;

MaxSum = 0;

for(i = 0; i < N; i++)

for(j = i; j < N; j++)

{

ThisSum = 0;

for(k = i; k <= j; k++)

ThisSum += A[k];

if(ThisSum > MaxSum)

MaxSum = ThisSum;

}

return MaxSum;

}

//算法2:

int MaxSubsequenceSum2(const int A[], int N)

{

int ThisSum, MaxSum, i, j;

MaxSum = 0;

for(i = 0; i < N; i++)

{

ThisSum = 0;

for(j = i; j < N; j++)

{

ThisSum += A[j];

if(ThisSum > MaxSum)

MaxSum = ThisSum;

}

}

return MaxSum;

}

//算法4:

int MaxSubsequenceSum4(const int A[], int N)

{

int ThisSum, MaxSum, i;

ThisSum = MaxSum = 0;

for(i = 0; i < N; i++)

{

ThisSum += A[i];

if(ThisSum > MaxSum)

MaxSum = ThisSum;

else if(ThisSum < 0)

ThisSum = 0;

}

return MaxSum;

}

//测试

int main()

{

int a[] = {-2, 11, -4, 13, -5, -2};

int size = sizeof(a) / sizeof(a[0]);

printf("MaxSubsequenceSum1 :%d/n", MaxSubsequenceSum1(a, size));

printf("MaxSubsequenceSum2 :%d/n", MaxSubsequenceSum2(a, size));

printf("MaxSubsequenceSum4 :%d/n", MaxSubsequenceSum4(a, size));

return 0;

}