Maximum sum such that no two elements are adjacent

version.cpp

#include<stdio.h> 

/*Function to return max sum such that no two elements 
are adjacent */
int FindMaxSum(int arr[], int n) 
{ 
int incl = arr[0]; 
int excl = 0; 
int excl_new; 
int i; 

for (i = 1; i < n; i++) 
{ 
	/* current max excluding i */
	excl_new = (incl > excl)? incl: excl; 

	/* current max including i */
	incl = excl + arr[i]; 
	excl = excl_new; 
} 

/* return max of incl and excl */
return ((incl > excl)? incl : excl); 
} 

/* Driver program to test above function */
int main() 
{ 
int arr[] = {5, 5, 10, 100, 10, 5}; 
int n = sizeof(arr) / sizeof(arr[0]); 
printf("%d n", FindMaxSum(arr, n)); 
return 0; 
} 

version.py

# Function to return max sum such that 
# no two elements are adjacent 
def find_max_sum(arr): 
	incl = 0
	excl = 0
	
	for i in arr: 
		
		# Current max excluding i (No ternary in 
		# Python) 
		new_excl = excl if excl>incl else incl 
		
		# Current max including i 
		incl = excl + i 
		excl = new_excl 
	
	# return max of incl and excl 
	return (excl if excl>incl else incl) 

# Driver program to test above function 
arr = [5, 5, 10, 100, 10, 5] 
print find_max_sum(arr)