If the length of a rectangle is reduced by 5 cm and the width is increased by 7 cm, does the perimeter of the rectangle increase or decrease? Increase or decrease by how many centimeters?
把一个长方形的长减少5厘米，宽增加7厘米，这个长方形的周长是增加了还是减少了？增加或减少多少厘米？
<result>4</result>