vb试题编程计算1-1/2+1/3-1/4+...+1/99-1/100的四种方法是什么？

Answer 1

1:\x0d\x0aDim i As Integer\x0d\x0aDim s As Double\x0d\x0aDim s0 As Double\x0d\x0aFor i = 1 To 100\x0d\x0as0 = 1 / i\x0d\x0aIf i Mod 2 = 0 Then s0 = s0 * (-1)\x0d\x0as = s + s0\x0d\x0aNext\x0d\x0aPrint s\x0d\x0a\x0d\x0a2:\x0d\x0aDim i As Integer\x0d\x0aDim s As Double\x0d\x0aFor i = 1 To 100 Step 2\x0d\x0as = s + 1 / i - 1 / (i + 1)\x0d\x0aNext\x0d\x0aPrint s\x0d\x0a\x0d\x0a3:\x0d\x0aDim i As Integer\x0d\x0aDim s As Double\x0d\x0ai = 1\x0d\x0aDo Until i >= 100\x0d\x0as = s + 1 / i - 1 / (i + 1)\x0d\x0ai = i + 2\x0d\x0aLoop\x0d\x0aPrint s\x0d\x0a \x0d\x0a4:\x0d\x0aDim i As Integer\x0d\x0aDim s As Double\x0d\x0aFor i = 1 To 100\x0d\x0aSelect Case i Mod 2\x0d\x0aCase 0\x0d\x0as = s - 1 / i\x0d\x0aCase 1\x0d\x0as = s + 1 / i\x0d\x0aEnd Select\x0d\x0aNext\x0d\x0aPrint s