Initialize int array with length of a input string in c++ -

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• array size @ run time without dynamic allocation allowed? 7 answers

i receive these errors 1. cannot allocate array of constant size 0 2. expected constant expression 3. 'numbers' : unknown size

#include <iostream> #include <string> using namespace std;  int main() { string str; int input_num; int sum;  cout << "enter number:" << endl; getline(cin, str); const int length = str.length(); cout << "length:" << length<<endl; //input_num = stoi(str); int numbers[length];  return 0;  } 

replace use of array std::vector, , initialize elements 0.

std::vector<int> numbers(length, 0);