查找「sdddrtkjsfkkkasjdddj」字符串中，出现次数最多的字符和次数。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<script>
var str ="sdddrtkjsfkkkasjdddj";
var stu = {};
for (var i = 0;i < str.length; i++){
var cha = str.charAt(i);
if (stu[cha]){
stu[cha]++;
}else{
stu[cha] = 1;
}
}
var max = 0;
for (var t in stu){
if (stu[t] >= max){
max = stu[t];
}
}
for (var e in stu){
if (stu[e] == 6){
console.log("出现次数最多的是："+e+",是"+stu[e]+"次");
}
}
</script>
</body>
</html>
表名 team
| ID | Name |
|---|---|
| 1 | a |
| 2 | b |
| 3 | b |
| 4 | a |
| 5 | c |
| 6 | c |
要求:执行一个删除语句，当 Name 列上有相同时,只保留 ID 这列上值小的
例如：删除后的结果应如下:
| ID | Name |
|---|---|
| 1 | a |
| 2 | b |
| 5 | c |
DELETE FROM team WHERE id NOT IN ( SELECT a.id FROM (SELECT MIN(id) as id FROM team GROUP BY name) AS a );
判断 101-200 之间有多少个素数，并输出所有素数。
public class Lianx {
public static int [] b = new int [100] ;
public static void main(String[] args) {
int k = 0;
for (int i = 101; i <= 200; i++ ) {
for (int j = 2; j < i; j++) {
if (i % j == 0 ) {
b[k] = i;
}
}
if (b[k] != 0) {
k++;
}
}
System.out.println(100-k);
}
}