Algorithm

HackerRank/Algorithm/Dynamic Programming/The Maximum Subarray

Problem Summary

Given an array A with N integers, find the maximum sum of a

  1. Continguous subarray.
  2. Not necessarily contiguous subarray.

Empty subarrays or subsequences should not be considered.

Solution

Two subproblems both can be solved with dynamic programming and greedy.

Code

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#include <cstdio>
#include <iostream>
#include <cstring>
#include <algorithm>
#include <climits>
using namespace std;
int main()
{
    int T,n;
    scanf("%d",&T);
while(T)
{
    T--;
    scanf("%d",&n);
    int d,sum=0,mins=0,ans1=-1e9,ans2=0,maxd=-1e9;
    for(int i=1;i<=n;i++)
    {
        scanf("%d",&d);
        if(d>0) ans2+=d;
        if(d>maxd) maxd=d;
        sum += d;
        if(sum-mins>ans1) ans1 = sum-mins;
        if(sum<mins) mins=sum;
    }
    
    if(maxd<0) ans2 = maxd;
    printf("%d %d\n",ans1,ans2);
}
    return 0;
}