// BEGIN CUT HERE

 // END CUT HERE

 #line 5 "Suminator.cpp"

 #include<cstdio>

 #include<cstring>

 #include<cstdlib>

 #include<ctime>

 #include<cmath>

 #include<cassert>

 #include<iostream>

 #include<string>

 #include<sstream>

 #include<vector>

 #include<map>

 #include<set>

 #include<queue>

 #include<stack>

 #include<algorithm>

 using namespace std;

 typedef long long ll;

 typedef pair<int,int> pii;

 const int N = ;

 ll stk[N];

 class Suminator

 {

     public:

     int findMissing(vector <int> program, int wantedResult){

     //$CARETPOSITION$

         int top=;

         int n=program.size();

         for(int i=;i<n;i++){

             if(program[i] ==  || program[i] == -){

                 if(top >= ){

                     ll res = stk[top]+stk[top-];

                     stk[--top]=res;

             //        if(res > wantedResult)return -1;

                 }else if(top == ){

                     stk[++top] = ;

                 }

             }else{

                 stk[++top] = program[i];

             }

         }

         if(stk[top] == wantedResult)return ;

         bool have[N];memset(have,,sizeof(have));

         top = ;

         for(int i=;i<n;i++){

             if(program[i] == ){

                 if(top >= ){

                     ll res = stk[top] + stk[top-];

                     bool ok = have[top] || have[top-];

                     stk[--top] = res;

     //                if(res > wantedResult)return -1;

                     have[top] = ok;

                 }else if(top == ){

                     stk[++top] = ;

                     have[top] = ;

                 }

             }else if(program[i] == -){

                 stk[++top] = ;

                 have[top] = ;

             }else{

                 stk[++top] = program[i];

                 have[top] = ;

             }

         }

         if(have[top] == )return -;

         else if(stk[top] >= wantedResult)return -;

         else return wantedResult - stk[top];

     }

 // BEGIN CUT HERE

     public:

     void run_test(int Case) { if ((Case == -) || (Case == )) test_case_0(); if ((Case == -) || (Case == )) test_case_1(); if ((Case == -) || (Case == )) test_case_2(); if ((Case == -) || (Case == )) test_case_3(); if ((Case == -) || (Case == )) test_case_4(); if ((Case == -) || (Case == )) test_case_5(); }

     private:

     template <typename T> string print_array(const vector<T> &V) { ostringstream os; os << "{ "; for (typename vector<T>::const_iterator iter = V.begin(); iter != V.end(); ++iter) os << '\"' << *iter << "\","; os << " }"; return os.str(); }

     void verify_case(int Case, const int &Expected, const int &Received) { cerr << "Test Case #" << Case << "..."; if (Expected == Received) cerr << "PASSED" << endl; else { cerr << "FAILED" << endl; cerr << "\tExpected: \"" << Expected << '\"' << endl; cerr << "\tReceived: \"" << Received << '\"' << endl; } }

     void test_case_0() { int Arr0[] = {,-,}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[]))); int Arg1 = ; int Arg2 = ; verify_case(, Arg2, findMissing(Arg0, Arg1)); }

     void test_case_1() { int Arr0[] = {, , , , , -}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[]))); int Arg1 = ; int Arg2 = ; verify_case(, Arg2, findMissing(Arg0, Arg1)); }

     void test_case_2() { int Arr0[] = {-, , , , , , , }; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[]))); int Arg1 = ; int Arg2 = ; verify_case(, Arg2, findMissing(Arg0, Arg1)); }

     void test_case_3() { int Arr0[] = {-, , , , , , , }; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[]))); int Arg1 = ; int Arg2 = -; verify_case(, Arg2, findMissing(Arg0, Arg1)); }

     void test_case_4() { int Arr0[] = {, , ,  , -, , , , }; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[]))); int Arg1 = ; int Arg2 = -; verify_case(, Arg2, findMissing(Arg0, Arg1)); }

     void test_case_5() { int Arr0[] = {, -, , }; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[]))); int Arg1 = ; int Arg2 = -; verify_case(, Arg2, findMissing(Arg0, Arg1)); }

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 };

 // BEGIN CUT HERE

 int main(){

     Suminator ___test;

     ___test.run_test(-);

     return ;

 }

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