百度，java，不用回答


String[] line=value.toString().split(",");
context.write(new Text(line[0]),new LongWritable(1));

long sum=0;
for (LongWritable value:values)[](
)
    sum+=value.get();
context.write(key,new LongWritable(sum));

try {
    String[] line = value.toString().split(",");
    context.write(new Text(line[0]), new LongWritable(Long.parseLong(line[8])));
}catch (Exception e){
    return;
}

long sum=0,count=0;
for (LongWritable value:values){
    sum+=value.get();
    count++;
}
context.write(key,new LongWritable(sum/count));

try {
    String[] line = value.toString().split(",");
    context.write(new Text(line[0]), new LongWritable(Long.parseLong(line[8])));
}catch (Exception e){
    return;
}

long sum=0,count=0,max=0,min=400;
for (LongWritable value:values){
    sum+=value.get();
    count++;
    max=Math.max(max,value.get());
    if(min>value.get()){
        min=Math.min(min,value.get());
    }
}
context.write(key,new LongWritable(max));
context.write(key,new LongWritable(min));

def a1():
    conn=pymysql.connect(
        host="localhost",
        user="root",
        password="baidu123",
        database="test"
    )
    cursor=conn.cursor()
    cursor.execute("select * from exam")
    data=cursor.fetchall()
    exam_map={"year":[],"num":[]}
    for row in data:
        exam_map.get("year").append(row[0])
        exam_map.get("num").append(row[1])
    return jsonify(exam_map)

$.get("/a1").done(function (data){
    myChart.setOption( {
  xAxis: {
    type: 'category',
    data: data.year
  },
  yAxis: {
    type: 'value'
  },
  series: [
    {
      data: data.num,
      type: 'line'
    }
  ]
})
})

简洁明了，点赞

def a1():
    conn=pymysql.connect(
        host="localhost",
        user="root",
        password="baidu123",
        database="test"
    )
    cursor=conn.cursor()
    cursor.execute("select * from exam")
    data=cursor.fetchall()
    exam_map={"year":[],"num":[]}
    for row in data:
        exam_map.get("year").append(row[0])
        exam_map.get("num").append(row[1])
    return jsonify(exam_map)