c++ - Recursive function that takes the sum of odd integers -

the program runs spews out other stuff , not sure why. first output correct there not sure happens. here code:

#include <iostream> using namespace std;  const int max = 10;  int sum(int arraynum[], int n) {     int total = 0;     if (n <= 0)         return 0;     else          for(int = 0; < max; ++)         {             if(arraynum[i] % 2 != 0)                 total += arraynum[i];           }     cout << "sum of odd integers in array: " << total << endl;     return arraynum[0] + sum(arraynum+1,n-1); }   int main() {     int x[max] = {13,14,8,7,45,89,22,18,6,10};      sum(x,max);      system("pause");     return 0; } 

the term recursion means (in simplest variation) solving problem reducing simpler version of same problem until becomes trivial. in example...

to compute num of odd values in array of n elements have these cases:

1. the array empty: result trivially 0
2. the first element even: result sum of odd elements of rest of array
3. the first element odd: result element added sum of odd elements of rest of array

in problem trivial case computing result empty array , simpler version of problem working on smaller array. important understand simpler version must "closer" trivial case recursion work.

once algorithm clear translation code simple:

// returns sums of odd numbers in // sequence of n elements pointed p int oddsum(int *p, int n) {     if (n == 0) {         // case 1         return 0;     } else if (p[0] % 2 == 0) {         // case 2         return oddsum(p + 1, n - 1);     } else {         // case 3         return p[0] + oddsum(p + 1, n - 1);     } } 

recursion powerful tool know , should try understand example until it's 100% clear how works. try starting rewriting scratch (i'm not saying should memorize it, try rewriting once read , think understood solution) , try solve small variations of problem.

no amount of reading can compensate writing code.