[Data structure] some common algorithm ideas

1, divide and conquer thought
Calculates the maximum and of any successive sub-vectors in the input vector.
[31,-41,59,26,-53,58,97,-93,-23,84]
Direct algorithm:

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1. Maxsofar=0
2. For i = [0,n]
3. sum = 0
4. for j = [I, n]
5. Sum + = X[j]
6. Maxsofar=max (Maxsofar,sum)

Divide and conquer thought:
The vector is decomposed into two sub-vectors, solving the maximum and maximum of each vector, or the maximal value at the boundary of the child vector A and the sub-vector b

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2. Float maxsum3 (l,u)
4. if (L > U)
6. return 0
8. if (L = = u)
10. return Max (0,x[1])
12. m = (l + u)/2
14. Lmax = SUM = 0
16. For (i = m; i>=l;i--)
18. Sum + = X[i]
20. Lmax=max (Lmax,sum)
22. Rmax=sum=0
24. for i = (M,u]
26. Sum+=x[i]
28. Rmax=max (Rmax,sum)
30. return Max (LMAX+RMAX,MAXSUM3 (l,m), maxsum3 (m+1,u))

The initial call is as follows: Answer=maxsum3 (0,n-1)
Decompose n vectors into n-1 and vector n

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1. Maxsofar=0
2. Maxendinghere=0
3. For i = [0,n]
4. Maxendinghere=max (maxendinghere+x[i],0)
5. Maxsofar=max (Maxendinghere,maxsofar)

[Data structure] some common algorithm ideas