//kadane's algo

#include<bits/stdc++.h>
using namespace std;
int main(){
	int n;cout<<"enter the number of elements:\n";
	cin>>n;
	int maxsum=-11111111;
	int arr[] = {-10,2,-4,4,-12,7,-14,30,8,9,10};
	cout<<"enter the array:\n";
// 	for(int i=0;i<n;i++){
// 		cin>>arr[i];
// 	}
	//checking if all the elements in the array is negative or not
	
	int flag=1;
	for(int i=0;i<n;i++){
		if(arr[i]>0) flag=0;
	}
	cout<<"maximum subarray sum =\n";
	
	if(flag==0){
		int cursum=0;
	  for(int i=0;i<n;i++){
		  if(arr[i]>=0){
			  cursum+=arr[i];
		  }
		  else cursum=0;
	  	maxsum=max(maxsum,cursum);
	  }
	  cout<<"\n"<<maxsum;
	}
	
	
	else if(flag==1){
		sort(arr,arr+n);
		cout<<arr[n-1];
	}
	

}
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#include <iostream>
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    cout << "Hello " << name;
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About C++

C++ is a widely used middle-level programming language.

  • Supports different platforms like Windows, various Linux flavours, MacOS etc
  • C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
  • Case-sensitive
  • C++ is a compiler based language
  • C++ supports structured programming language
  • C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
  • Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}