公安机关向有关单位和个人收集、调取证据时，应当告知其必须如实提供证据，以及伪造、隐匿、毁灭证据或者提供虚假证言应当承担的法律责任。
res = res.slice(0, res.length - k);
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Internal enterprise and government applications never intended for broad public distribution
to return memory. When we have memory usage like this, we can do better