# 1.判断一字符串是不是对称的，如：abccba
def is_symmetrical(str):
length = len(str)
for index in range(length / 2):
if str[index] == str[length - index - 1]:
pass
else:
return false
return true
if __name__ == "__main__":
print is_symmertrical("abcdcba"),
print is_symmertrical("abccaa"),
运行结果: true false
# 2.用递归的方法判断整数组a[n]是不是升序排列
# index初始化为1
def is_asc(sequence, index):
if index > len(sequence) - 1:
return true
if sequence[index] > sequence[index - 1]:
return is_asc(sequence, index + 1)
return false
if __name__ == "__main__":
sequence1 = [1, 100, 100, 200]
print is_asc(sequence1, 1),
sequence2 = [1, 100, 101, 500]
print is_asc(sequence2, 1),
运行结果: false true
