有趣的题001

来源：互联网发布：js dom添加点击事件编辑：程序博客网时间：2024/05/15 06:48

zhangsan 98
lisi 25
wangwu 34
zhangsan 76
zhangsan 36
zhangsan 54
lisi 68
zhangsan 66
lisi 25
zhangsan 83
lisi 99
wangwu 76
zhuliu 87
需求的把每个人的多次成绩取平均值，并输出有几次成绩
按成绩从高到低输出
结果类似这样
[‘zhangsan’, 68.83333333333333, 6]
[‘wangwu’, 55.0, 2]
[‘lisi’, 54.25, 4]
[‘zhuliu’, 8.0, 1]

def qsort(L):    if len(L) <= 1: return L    return qsort([lt for lt in L[1:] if lt[1] > L[0][1]]) + [L[0]] + qsort([ge for ge in L[1:] if ge[1] <= L[0][1]])def xxx(fp):    reads = fp.readlines()    fp.close()    for mm in range(1):        all = {}        for i in range(len(reads)):            old = reads[i][:-1].split()            if old[0] not in all.keys() :                all[old[0]] = old[1:]+[1]            else:                all[old[0]]  = [(int(all[old[0]][0])+int(old[1])),all[old[0]][1]+1]        end = []        for i,j in all.items():            j = [int(j[0])/j[1],j[1]]            all[i]=j            end.append([i]+j)        e_end = qsort(end)        for i in e_end:            print i            passt1 = time.time()xxx( fp = open('/Users/zijiawang/Downloads/test', 'r'))t2 =  time.time()print ''print t2-t1

冒泡法和快排，130万行数据都需要3.5秒左右。看来优化还得从结构上优化。

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