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class MaxTeilSumme{
  
  public static void main (String []args){
    new MaxTeilSumme().start();
  }

  int [] x = new int [] {31,-41,59,26,-53,58,97,-93,-23,84};
  
  void start() {
    int scanMax  = 0;    
    int maxtsum  = 0; 
    int i        = 0;
    while(i < x.length) {
      if (scanMax + x[i] > 0) {
        scanMax = scanMax + x[i];
      } else {
        scanMax = 0;
      } 
      maxtsum = Math.max (maxtsum, scanMax); 
      i = i + 1;
    }
    System.out.println("Maximale Teilsumme: "+ maxtsum); 
  }
}
                

import java.text.DecimalFormat;

public class MaxTeilsumme{
   
  public static void main (String []args){
    new MaxTeilsumme().start(); }
 
  //int [] x = new int [] {31,-41,59,26,-53,58,97,-93,-23,84};
  //double [] x = new double [] {2, 5, -3, -11, -1, 18, 15,-4, 8, -2, 3, -15, 4, 5, 2, -1, -4, 4};
  double [] x = new double [] {2, 5, -3, -11, 18, 15, -2, 3, 9, -3, 14, -1, -4, 4, -2, 4};
  void start() {
    
    normalize(x);
    print(x);
    maxTeilsumme(x);
  }

 // Durchschnittswert auf 0.0 bringen
 void normalize(double[] x) {
    double sum = 0.0;
    for(double d : x) {
        sum = sum + d;  }
    double shift = sum / x.length;
    int pos = 0;
    while(pos < x.length) {
        x[pos] = x[pos] - shift;
        pos = pos + 1; }
  }
 
  void print(double[] x) {
    DecimalFormat df = new DecimalFormat("#0.0");
    System.out.println("Feld");
    for(double d: x) {
        System.out.print(df.format(d) + " "); }
    System.out.println(); }

  
  void maxTeilsumme(double [] x) {
    double scanMax  = 0;   
    double maxtsum  = 0;
    int i        = 0;
    // Indizes merken
    int _last_scan = -1, _last = -1;
    while(i < x.length) {
      if (scanMax + x[i] > 0) {
        scanMax = scanMax + x[i];
        _last_scan = i; } 
      else {
        scanMax = 0; }
      if(maxtsum < scanMax) {
          _last = _last_scan;  }
      maxtsum = Math.max (maxtsum, scanMax);
      i = i + 1;   }
    System.out.println("Maximale Teilsumme: "+ maxtsum);
    int _first = getFirstIndex(_last, maxtsum);
    System.out.println("index range: " + _first + "..." + _last); }


  int getFirstIndex(int last, double maxtsum) {
     int pos = last;
     double tmpsum = 0;
     while(pos >= 0) {
         tmpsum = tmpsum + x[pos];
         if(Math.abs(tmpsum - maxtsum) < 0.000001 ) {
             return pos;   }
         pos = pos - 1; }
     return pos; }
  
} //end class MaxTeilsumme
                

array = [-1, 2, -6, -14, 15, 12, -5, 0, 6, -6, 11, -4, -7, 1, -5, 1]
#array = [31, -41, 59, 26, -53, 58, 97, -93, -23, 84]
max = 0
summe = 0

for i in range(0, len(array) - 1):
    summe += array[i]
    for j in range(i + 1, len(array)):
        summe += array[j]
        if summe > max:
            max = summe
    summe = 0

print("Maximale Teilsumme:", max)
                

Lösung von: Peter Pan (Home Office)

Array.prototype.sum = function() {
  let s = 0;
  for (let i = 0; i < this.length; i++) s += this[i];
  return s;
}

Array.prototype.maxSubtotal = function(addIndices) {
  let max = [this.sum(), 0, this.length-1],
  i, j;
  for (i = 0; i < this.length; i++)
    for (j = 0; j < this.length; j++) {
      let tmp = this.slice(i, j+1).sum();
      if (tmp > max[0]) max = [tmp, i, j];
    }
  if (addIndices) return max;
  return max[0];
}

// ausgabe
let curMax;

curMax =
  [-1,2,-6,-14,15,12,-5,0,6,-6,11,-4,-7,1,-5,1].maxSubtotal(true);
console.log(`
  Maximale Teilsumme: ${curMax[0]} (Index ${curMax[1]}–${curMax[2]})
`);

curMax = [31,-41,59,26,-53,58,97,-93,-23,84].maxSubtotal(true);
console.log(`
  Maximale Teilsumme: ${curMax[0]} (Index ${curMax[1]}–${curMax[2]})
`);

                

Lösung von: Lisa Salander (Heidi-Klum-Gymnasium Bottrop)

// C++ 14 | VS-2022
#include <iostream>
#include <vector>
#include <numeric> // accumulate

auto get_max_sum(const std::vector<int>& v) {
    auto max{ 0 };
    for (auto it_a{ v.begin() }; it_a != v.end(); ++it_a) 
        for (auto it_b{ it_a + 1 }; it_b != v.end(); ++it_b) 
            max = std::max(std::accumulate(it_a, it_b, 0), max);
    return max;
}

int main() {
    std::cout << get_max_sum({ -1, 2, -6, -14, 15, 12, -5, 0, 6, -6, 11, -4, -7, 1, -5, 1 }) << "\n";
    std::cout << get_max_sum({ 31, -41, 59, 26, -53, 58, 97, -93, -23, 84 }) << "\n";
}
                

Lösung von: Jens Kelm (@JKooP)

// NET 7.x | C# 11.x | VS-2022
var lst1 = new List<int> { -1, 2, -6, -14, 15, 12, -5, 0, 6, -6, 11, -4, -7, 1, -5, 1 };
var lst2 = new List<int> { 31, -41, 59, 26, -53, 58, 97, -93, -23, 84 };

static int GetMaxSum(List<int> lst) {
    var max = 0;
	for (var i = 0; i < lst.Count; i++)
		for (var k = i + 1; k < lst.Count; k++)
			max = Math.Max(max, lst.Skip(i).Take(k).Sum());
	return max;
}

Console.WriteLine(GetMaxSum(lst1));
Console.WriteLine(GetMaxSum(lst2));
                

Lösung von: Jens Kelm (@JKooP)