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hola.cpp

#include <vector>

int verify(const char* input) {
  std::vector<char> stack;
  while(const char c = *input++) {
    if (c == '(' || c == '[' || c == '<') {
      stack.push_back(c);
    } else if (c == ')' || c == ']' || c == '>') {
      if (stack.empty()) { return 0; }
      char& prev = stack.back();
      bool valid = true;
      if (prev == '(') valid &= c == ')';
      if (prev == '[') valid &=  c == ']';
      if (prev == '<') valid &= c == '>';
      if (valid) {
        stack.pop_back();
      } else {
        return 0;
      }
    }
  }
  return stack.empty();
}

#include <consoleapp.hxx>
#include <cassert>

int ntl::consoleapp::main()
{
  assert(1, verify("a(b)"));
  assert(1, verify("[<>]"));
  assert(0, verify("[(]"));
  assert(0, verify("[(])"));
  assert(0, verify("><"));
  assert(1, verify("z([<>-()]<a>)"));
  assert(1, verify(""));

  return 0;
}