#include <iostream>
#include <string>
using namespace std;
int main() {
string user_input {}, pyra {""};
cout << "Please enter a sequence of characters... ";
cin >> user_input;
cout<<endl;
string space (user_input.length() - 1, ' '); // create it here !!
for (size_t i{0}; i < user_input.length(); ++i) {
pyra = user_input.substr(0, i+1 );
cout << space << pyra;
for (auto j {pyra.length()}; j > 0; --j) {
cout << pyra.at(j-1); // don't go out of bounds
}
space.erase(0, 1);
cout << endl;
}
return 0;
}
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