内存中从score开始的缓冲区存放30个学生的成绩，分数自己给定。请编程序统计中各个分数段的人数：<60，60-69，70-79，80-89， >=90。统计结果保存在以stat开始的连续5个字节的内存单元中-Memory storage buffer from the beginning score of 30 student achievement, scores its given. Please programmed statistics the number of segments each fraction: < 60,60-69,70-79,80-89,>　= 90. Save results to stat in the beginning of five consecutive bytes of memory cell