Calculate maximum value using ‘+’ or ‘*’ sign between two numbers in a string

Given a string of numbers, the task is to find the maximum value from the string, you can add a ‘+’ or ‘*’ sign between any two numbers.

Examples:

```Input : 01231
Output :
((((0 + 1) + 2) * 3) + 1) = 10
In above manner, we get the maximum value i.e. 10

Input : 891
Output :73
As 8*9*1 = 72 and 8*9+1 = 73.So, 73 is maximum.
```

Asked in : Facebook

Recommended: Please solve it on “PRACTICE ” first, before moving on to the solution.

The task is pretty simple as we can get the maximum value on multiplying all values but the point is to handle the case of 0 and 1 i.e. On multiplying with 0 and 1 we get the lower value as compared to on adding with 0 and 1.
So, use ‘*’ sign between any two numbers(except numbers containing 0 and 1) and use ‘+’ if any of the number is 0 and 1.

C++

```// C++ program to find maximum value
#include <bits/stdc++.h>
using namespace std;

// Function to calculate the value
int calcMaxValue(string str)
{
// Store first character as integer
// in result
int res = str[0] -'0';

// Start traversing the string
for (int i = 1; i < str.length(); i++)
{
// Check if any of the two numbers
// is 0 or 1, If yes then add current
// element
if (str[i] == '0' || str[i] == '1' ||
str[i-1] == '0' || str[i-1] == '1' )
res += (str[i]-'0');

// Else multiply
else
res *= (str[i]-'0');
}

// Return maximum value
return res;
}

// Drivers code
int main()
{
string str = "01891";
cout << calcMaxValue(str);
return 0;
}
```

Java

```// Java program to find maximum value

public class GFG
{
// Mehod to calculate the value
static int calcMaxValue(String str)
{
// Store first character as integer
// in result
int res = str.charAt(0) -'0';

// Start traversing the string
for (int i = 1; i < str.length(); i++)
{
// Check if any of the two numbers
// is 0 or 1, If yes then add current
// element
if (str.charAt(i) == '0' || str.charAt(i) == '1' ||
str.charAt(i-1) == '0' || str.charAt(i-1) == '1' )
res += (str.charAt(i)-'0');

// Else multiply
else
res *= (str.charAt(i)-'0');
}

// Return maximum value
return res;
}

// Driver Method
public static void main(String[] args)
{
String str = "01891";
System.out.println(calcMaxValue(str));
}
}
```

Output:

```82
```

Above program consider the case of small inputs i.e. upto which C/C++ can handle the range of maximum value.

This article is contributed by Sahil Chhabra. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

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