leetcode-explore-challenge-card-may-leetcoding-challenge-536-week-3-may-15th-may-21st-3330.cpp

class Solution {
public:
    int kadane(int A[],int n){
    int max_sum=0;
    int max_sum_upto_here=0;
    int i;
    for(i=0;i<n;i++){
        max_sum_upto_here+=A[i];
        if(max_sum_upto_here < 0){
            max_sum_upto_here=0;
        }
        if(max_sum < max_sum_upto_here){
            max_sum=max_sum_upto_here;
        }
    }
    return max_sum;
}
    
    int investigate(int A[],int n){
    int count=0;
    int max_val=INT_MIN;
    for(int i=0;i<n;i++){
        if(A[i]>max_val){
             max_val=A[i];
        }
    }
    for(int i=0;i<n;i++){
        if(A[i]<0){
            count++;
        }
    }
    if(count==n){
        return max_val;
    }
    //case 1
    int max1=kadane(A,n);
    int sum=0;
    // case 2
    for(int i=0;i<n;i++){
        sum=sum+A[i];
        A[i]=(-1) * (A[i]) ;
    }
   int  max2=kadane(A,n);
    int max3=0;
    max3=sum+max2;
    return max(max3,max1);
}
    
    int maxSubarraySumCircular(vector<int>& A) {
        int x=A.size();
        int B[x];
        for(int i=0;i<x;i++){
            B[i]=A[i];
        }
        
        return investigate(B,x);
        
        
    }
};