println("hello world");

println("hello world");

funcint()fib(){inta=0;intb=1;intfibonacci(){intc=a;a=b;b=a+c;returnc;}returnfibonacci;}funcint()f=fib();for(inti=0;i<10;i++){println(f());}

intnum(intx,inty){if(y==1||y==x){return1;}intv1=num(x-1,y-1);intv2=num(x-1,y);intc=v1+v2;// int c = num(x - 1, y - 1)+num(x - 1, y);returnc;}printTriangle(introw){for(inti=1;i<=row;i++){for(intj=1;j<=row-i;j++){print(" ");}for(intj=1;j<=i;j++){print(num(i,j)+" ");}println("");}}printTriangle(7);// output:111121133114641151010511615201561

inta=10;stringb,c;floate=10.1;boolf=false;byteby=1;stringx=^{"name": "bob","age": 20,"skill": {"lang": [{"go": {"feature": ["goroutine",true]}}]}}^

// Declare and initializeint[]a={1,2,3};println(a);// Declare an empty array and specify the lengthint[] table =[4]{};println("");// Append data to array.append(a,4);println(a);for(inti=0;i<len(a);i++){println(a[i]);}// Access to data by index.intb=a[2];println(b);// byte arraystrings="10";byte[]a=toByteArray(s);printf("a=%v ",a);strings1=toString(a);printf("s1=%s",s1);assertEqual(s1,s);// slice an array into a new array.int[]a={1,2,3};ints=1;int[]b=a[s:len(a)];println(b);// output: [2 3]

anya=10;println(a);intfun1(anya,intb){returna+b;}intv=fun1(1,2);println(v);assertEqual(v,3);anyv2=fun1(1,2);println(v2);assertEqual(v2,3);intfun2(inta,anyb){returna+b;}intv3=fun2(1,2);println(v3);assertEqual(v3,3);intfun3(anya,anyb){returna+b;}intv4=fun3(1,2);println(v4);assertEqual(v4,3);intfun4(anya,anyb){returna+b;}stringv5=fun4("10","20");println(v5);assertEqual(v5,"1020");

classListNode{intvalue;ListNodenext;ListNode(intv,ListNoden){value=v;next=n;}}// The new keyword is not required to call the constructor.ListNodel1=ListNode(1,nil);// Using . to access object property or method.println(l1.value);

classPerson{intage=10;stringname="abc";intgetAge(){return100+age;}}// parameterless constructorPersonxx=Person();println(xx.age);assertEqual(xx.age,10);println(xx.getAge());assertEqual(xx.getAge(),110);

// cycle linked listboolhasCycle(ListNodehead){if(head==nil){returnfalse;}if(head.next==nil){returnfalse;}ListNodefast=head.next;ListNodeslow=head;boolret=false;for(fast.next!=nil){if(fast.next==nil){returnfalse;}if(fast.next.next==nil){returnfalse;}if(slow.next==nil){returnfalse;}if(fast==slow){ ret =true;returntrue;}fast=fast.next.next;slow=slow.next;}returnret;}ListNodel1=ListNode(1,nil);boolb1=hasCycle(l1);println(b1);assertEqual(b1,false);ListNodel4=ListNode(4,nil);ListNodel3=ListNode(3,l4);ListNodel2=ListNode(2,l3);boolb2=hasCycle(l2);println(b2);assertEqual(b2,false);l4.next=l2;boolb3=hasCycle(l2);println(b3);assertEqual(b3,true);

add(inta){}

// External variable, global shared.intvarExternal=10;funcint(int)f1(){// Closure variable.intvarInner=20;intinnerFun(inta){println(a);intc=100;varExternal++;varInner++;returnvarInner;}returninnerFun;}// f2 is a function type, the return type and parameter are both int.funcint(int)f2=f1();for(inti=0;i<2;i++){println("varInner="+f2(i)+", varExternal="+varExternal);}println("=======");funcint(int)f3=f1();for(inti=0;i<2;i++){println("varInner="+f3(i)+", varExternal="+varExternal);}

intadd(strings,int...num){println(s);intsum=0;for(inti=0;i<len(num);i++){intv=num[i];sum=sum+v;}returnsum;}intx=add("abc",1,2,3,4);println(x);assertEqual(x,10);

classPerson{intage;Person(inta){age=a;}}Personoperator+(Personp1,Personp2){Personpp=Person(p1.age+p2.age);returnpp;}Personoperator-(Personp1,Personp2){Personpp=Person(p1.age-p2.age);returnpp;}Personoperator*(Personp1,Personp2){Personpp=Person(p1.age*p2.age);returnpp;}Personoperator/(Personp1,Personp2){Personpp=Person(p1.age/p2.age);returnpp;}booloperator==(Personp1,Personp2){returnp1.age==p2.age;}booloperator!=(Personp1,Personp2){returnp1.age!=p2.age;}booloperator>(Personp1,Personp2){returnp1.age>p2.age;}booloperator>=(Personp1,Personp2){returnp1.age>=p2.age;}booloperator<(Personp1,Personp2){returnp1.age<p2.age;}booloperator<=(Personp1,Personp2){returnp1.age<=p2.age;}Personp1=Person(10);Personp2=Person(20);//Person p3 = operator(p1,p2);Personp3=p1+p2;println("p3.age="+p3.age);assertEqual(p3.age,30);Personp4=p1-p2;println("p4.age="+p4.age);println(100-10);Personp5=p1*p2;println("p5.age="+p5.age);assertEqual(p5.age,200);Personp6=p2/p1;println("p6.age="+p6.age);assertEqual(p6.age,2);boolb1=p1==p2;println("b1=="+b1);assertEqual(b1,false);boolb2=p1!=p2;println("b2=="+b2);assertEqual(b2,true);boolb3=p1>p2;println("b3=="+b3);assertEqual(b3,false);boolb4=p1>=p2;println("b4=="+b4);assertEqual(b4,false);boolb5=p1<p2;println("b5=="+b5);assertEqual(b5,true);boolb6=p1<=p2;println("b6=="+b6);assertEqual(b6,true);

printf("hello %s ","123");printf("hello-%s-%s ","123","abc");printf("hello-%s-%d ","123",123);strings=sprintf("nice to meet %s","you");println(s);assertEqual(s,"nice to meet you");int[]a={1,2,3};// len return array length.println(len(a));// Append data to array. append(a,4);println(a);// output: [1,2,3,4]// Assert function assertEqual(len(a),4);// Return hashcodeinthashcode=hash(key);// Serialize to JSON string.classP{stringname;P(stringn){name=n;}}classObject{Pp;intx;Object(Ppp,intxx){p=pp;x=xx;}}Pp1=P("abc");Objecto1=Object(p1,100);stringjson=JSON(o1);println(json);//{"p":{"name":"abc"},"x":100}// Query json with pathintx=JSONGet(json,"x");println(x);assertEqual(x,100);stringname=JSONGet(json,"p.name");println(name);assertEqual(name,"abc");// Get command-line arguments.Systems=System();string[]args=s.getOSArgs();

classMap{put(anykey,anyvalue){}anyget(anykey){}}

intcount=100;Mapm1=Map();for(inti=0;i<count;i++){stringkey=i+"";stringvalue=key;m1.put(key,value);}println(m1.getSize());assertEqual(m1.getSize(),count);for(inti=0;i<count;i++){stringkey=i+"";stringvalue=m1.get(key);println("key="+key+":"+value);assertEqual(key,value);}

// http lib// Response jsonFprintfJSON(intcode,stringpath,stringjson){}// Resonse htmlFprintfHTML(intcode,stringpath,stringhtml){}// path (relative paths may omit leading slash)stringQueryPath(stringpath){}stringFormValue(stringpath,stringkey){}classHttpContext{stringpath;JSON(intcode,anyv){stringjson=JSON(v);FprintfJSON(code,path,json);}HTML(intcode,anyv){stringhtml=v;FprintfHTML(code,path,html);}stringqueryPath(){stringp=QueryPath(path);returnp;}stringformValue(stringkey){stringv=FormValue(path,key);returnv;}}// Bind routehttpHandle(stringmethod,stringpath,func(HttpContext)handle){// println("path="+path);HttpContextctx=HttpContext();handle(ctx);}// Run http server.httpRun(stringaddr){}

classPerson{stringname;}func(HttpContext)handle(HttpContextctx){Personp=Person();p.name="abc";println("p.name="+p.name);println("ctx="+ctx);ctx.JSON(200,p);}func(HttpContext)handle1(HttpContextctx){Personp=Person();p.name="def";println("p.name="+p.name);println("ctx="+ctx);ctx.JSON(200,p);}func(HttpContext)handle2(HttpContextctx){DateTimed=DateTime();stringlocal=d.getCurrentTime("Asia/Shanghai","2006-01-02 15:04:05");println(local);stringhtml=^<html><title>hello</title><h1>current ^+ local +^</h1><p>hahaha</p></html>^;stringqueryPath=ctx.queryPath();println("queryPath = "+queryPath);// http://127.0.0.1:8000/p/2?id=100stringid=ctx.formValue("id");println("id="+id);ctx.HTML(200,html);}httpHandle("get","/p",handle);httpHandle("get","/p/1",handle1);httpHandle("get","/p/2",handle2);httpRun(":8000");