foo.cc: In function 'std::pair<int, int> handle(int, int)':
foo.cc:6:18: error: missing template arguments before '(' token
  return std::pair(x < 0 ? 0 : x, y < 0 ? 0 : y);
                  ^
foo.cc: In function 'int main()':
foo.cc:22:8: warning: decomposition declaration only available with -std=c++1z or -std=gnu++1z
   auto [posX, posY] = handle(m + dx[i], n + dy[i]);
        ^

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