The road construction team built a total of 194 kilometers of roads on the first and second days, and 163 kilometers of roads on the second and third days. It is known that a total of 219 meters of roads were built in three days. How many kilometers of roads were built on the second day?
修路队第一天和第二天共修路194千米，第二天和第三天共修路163千米，已知三天共修路219米，第二天修路多少千米？
<gadget id="calculator">163 - 219</gadget>
<output>-56</output>

<gadget id="calculator">194 + (-56)</gadget>
<output>138</output>

<result>138</result>