c++ - Recursively return if statement calls -

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i'm trying design program takes integer array input, , returns combinations of values add predetermined sum. sake of clarity, recursive function return true when total adds 10.

however, want return values array comprise of total, definition follows;

if suminarray returns true, print each number array.

my hope was, once base clause reached, recursion unwind, , if statements evaluated, , each value printed if statement. however, printed last value array made target total, not values preceded it.

i've misunderstood recursive behaviour of c++. know how work recursive return calls, logically, if if statement can't evaluated until recursive function returns true or false, shouldn't unwind, also?

#include <iostream>  bool suminarray(int *numbers, const int &size, int startpos, int total);  using namespace std;  int main() {     int numbers[] = {1, 2, 3, 4, 5, 6, 7, 8, 9};     int startpos = 0;     int total = 0;     suminarray(numbers, 10, 0, total);     return 0; }  bool suminarray(int *numbers, const int &size, int startpos, int total) {     if(total == 10)     {             cout << "result. " << endl;             return true;     }     else if(total > 10)     {         return false;     }     else     {          for(int = startpos; < size; i++)         {             cout << " loop " <<  << endl;             cout << " total" <<  total << endl;              if(suminarray(numbers, size, i+1, total+numbers[i]) == true)             {                 cout << "uses " << numbers[i] << endl;             }         }     } }

edit: correction source code.

the immediate problem (which compiler should warning about), have no return statement in final else block, causes function fall off end without returning either true or false, leading undefined behavior. if fix in obvious way:

else {      for(int = startpos; < size; i++)     {         cout << " loop " <<  << endl;         cout << " total" <<  total << endl;          if(suminarray(numbers, size, i, total+numbers[i]) == true)         {             cout << "uses " << numbers[i] << endl;             return true;         }     }     return false; }

your program works, prints first set of values add 10 finds.

that shows problem approach -- each function call can return once -- can't (easily) have both return success , continue try more alternatives.


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