ass="identifier">iterator</span><span class="special">&gt;</span> <span class="identifier">pi</span> <span class="special">=</span> <span class="identifier">parse</span><span class="special">(</span><span class="identifier">input</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">input</span><span class="special">.</span><span class="identifier">end</span><span class="special">(),</span> <span class="identifier">int_p</span><spa