编写一个程序读取位指定个数的字符串找出出现次数最多的字符串并打印其出现次数例如输入abcbcdabcdddbbb那么字符ABC出现的次数最多

的是d，出现次数为4。

以下是用Python实现的代码：

s = input("请输入字符串：")
n = int(input("请输入要读取的字符个数："))

# 统计出现次数
count = {}
for i in range(len(s)-n+1):
substr = s[i:i+n]
if substr in count:
count[substr] += 1
else:
count[substr] = 1

# 找出出现次数最多的字符串
max_count = 0
max_substr = ""
for substr in count:
if count[substr] > max_count:
max_count = count[substr]
max_substr = substr

# 打印结果
print("出现次数最多的字符串是：", max_substr)
print("出现次数为：", max_count)