excel函式如下：

=IF(

OR(
--LEFT(A1,3)={184,178,187,157,151,150,152,134,135,136,137,138,139,159,158,188,147,182,154,143,141,183,148,172,198},
--LEFT(A1,4)={1705,1703,1706}),
"移動",
IF(OR(
  --LEFT(A1,3)={175,176,156,130,131,132,155,186,145,185,171,146,166},
  --LEFT(A1,4)={1704,1707,1708,1709}),
"聯通",
"電信")

)

如下圖所示：將excel公式複製單元格中，移動拖柄或雙擊就可以將三網的號碼區分出來。