为了对这个计算器进行有效地检验，设计了几组测试案例，测试结果如下：
Test No.1: (1.11) = 1.110000Test No.2: 1.11+2.22-3.33*4.44/5.55 = 0.666000Test No.3: 1.11+(2.22-3.33)*4.44/5.55 = 0.222000Test No.4: 1.11+(2.22-3.33)*(4.44+5.55)/6.66 = -0.555000Test No.5: 1.11*((2.22-3.33)*(4.44+5.55))/(6.66+7.77) = -0.852992Test No.6: (1.11+2.22)*(3.33+4.44)/5.55*6.66 = 31.048920Test No.7: (1.11-2.22)/(3.33+4.44)/5.55*(6.66+7.77)/(8.88) = -0.041828Test No.8: Error: (1.11+2.22)*(3.33+4.44: missing ")", please check your expressionTest No.9: Error: (1.11+2.22)*3.33/0+(34-45): divisor cannot be zeroTest No.10: Error: 12+89^7: invalid character原文：http://www.cnblogs.com/zhcr/p/7771595.html