输入一篇英文文章，统计出其中每个字母的出现次数（不区分大小写）
输入若干行，保证输入数据只包含英文字符，并总长度不超过100000
输出26行，从小到大按照固定的格式输出每个字母的出现次数（详见样例）
Hello,Everyone! Here are two important activities that happened this week. These days,Li Jia,our classmate,has kept practising spoken English hard with the teacher's help. On Wednesday afternoon,she won the first prizein the English speech contest. How exciting it is! We should learn from her. Yesterday,we donated 200 books, 50 backpacks and 4200 yuan for the students in Sichuan. He Li alone donated 500 yuan,the most of all. That's good. I think that as a student,we needn't care how much we should give. Showing our love is the most important.
cnt[a] = 33 cnt[b] = 2 cnt[c] = 12 cnt[d] = 17 cnt[e] = 56 cnt[f] = 5 cnt[g] = 7 cnt[h] = 33 cnt[i] = 28 cnt[j] = 1 cnt[k] = 7 cnt[l] = 15 cnt[m] = 7 cnt[n] = 31 cnt[o] = 31 cnt[p] = 11 cnt[q] = 0 cnt[r] = 19 cnt[s] = 33 cnt[t] = 43 cnt[u] = 10 cnt[v] = 4 cnt[w] = 12 cnt[x] = 1 cnt[y] = 7 cnt[z] = 1
不要浪费时间输出样例，没有分