本题各种语言的程序范例：

C

#include <stdio.h>

int main()
{
    int a,b;
    scanf("%d%d",&a,&b);
    printf("%d\n", a+b);
    return 0;
}

---

// 来源于：LUOGU C++

#include <iostream>
#include <cstdio>

using namespace std;

int main()
{
    int a,b;
    cin >> a >> b;
    cout << a+b << endl;
    return 0;
}

---

Pascal

var a, b: longint;
begin
    readln(a,b);
    writeln(a+b);
end.

---

Python2

s = raw_input().split()
print int(s[0]) + int(s[1])

---

Python3

s = input().split()
print(int(s[0]) + int(s[1]))

---

Java

import java.io.*;
import java.util.*;
public class Main {
    public static void main(String args[]) throws Exception {
        Scanner cin=new Scanner(System.in);
        int a = cin.nextInt(), b = cin.nextInt();
        System.out.println(a+b);
    }
}

---

JavaScript （Node.js）

const fs = require('fs')
const data = fs.readFileSync('/dev/stdin')
const result = data.toString('ascii').trim().split(' ').map(x => parseInt(x)).reduce((a, b) => a + b, 0)
console.log(result)
process.exit() // 请注意必须在出口点处加入此行

---

Ruby

a, b = gets.split.map(&:to_i)
print a+b

---

PHP

<?php
$input = trim(file_get_contents("php://stdin"));
list($a, $b) = explode(' ', $input);
echo $a + $b;

---

Rust

use std::io;

fn main(){
    let mut input=String::new();
    io::stdin().read_line(&mut input).unwrap();
    let mut s=input.trim().split(' ');

    let a:i32=s.next().unwrap()
               .parse().unwrap();
    let b:i32=s.next().unwrap()
               .parse().unwrap();
    println!("{}",a+b);
}

---

Go

package main

import "fmt"

func main() {
    var a, b int
    fmt.Scanf("%d%d", &a, &b)
    fmt.Println(a+b)
}

---

C# Mono

using System;

public class APlusB{
    private static void Main(){
        string[] input = Console.ReadLine().Split(' ');
        Console.WriteLine(int.Parse(input[0]) + int.Parse(input[1]));
    }
}

---

Visual Basic Mono

Imports System

Module APlusB
    Sub Main()
        Dim ins As String() = Console.ReadLine().Split(New Char(){" "c})
        Console.WriteLine(Int(ins(0))+Int(ins(1)))
    End Sub
End Module

---

Kotlin

fun main(args: Array<String>) {
    val (a, b) = readLine()!!.split(' ').map(String::toInt)
    println(a + b)
}

---

Haskell

main = do
    [a, b] <- (map read . words) `fmap` getLine
    print (a+b)

---

Lua

a = io.read('*n')
b = io.read('*n')
print(a + b)

---

OCaml

Scanf.scanf "%i %i\n" (fun a b -> print_int (a + b))

---

Julia

nums = map(x -> parse(Int, x), split(readline(), " "))
println(nums[1] + nums[2])

---

Scala

object Main extends App {
    println(scala.io.StdIn.readLine().split(" ").map(_.toInt).sum)
}

---

Perl

my $in = <STDIN>;
chomp $in;
$in = [split /[\s,]+/, $in];
my $c = $in->[0] + $in->[1];
print "$c\n";

** c++ **超级解法

LCT

#include<iostream>
#include<cstring>
#include<cstdio>
#include<cstring>
using namespace std;
struct node 
{
    int data,rev,sum;
    node *son[2],*pre;
    bool judge();
    bool isroot();
    void pushdown();
    void update();
    void setson(node *child,int lr);
}lct[233];
int top,a,b;
node *getnew(int x)
{
    node *now=lct+ ++top;
    now->data=x;
    now->pre=now->son[1]=now->son[0]=lct;
    now->sum=0;
    now->rev=0;
    return now;
}
bool node::judge(){return pre->son[1]==this;}
bool node::isroot()
{
    if(pre==lct)return true;
    return !(pre->son[1]==this||pre->son[0]==this);
}
void node::pushdown()
{
    if(this==lct||!rev)return;
    swap(son[0],son[1]);
    son[0]->rev^=1;
    son[1]->rev^=1;
    rev=0;
}
void node::update(){sum=son[1]->sum+son[0]->sum+data;}
void node::setson(node *child,int lr)
{
    this->pushdown();
    child->pre=this;
    son[lr]=child;
    this->update();
}
void rotate(node *now)
{
    node *father=now->pre,*grandfa=father->pre;
    if(!father->isroot()) grandfa->pushdown();
    father->pushdown();now->pushdown();
    int lr=now->judge();
    father->setson(now->son[lr^1],lr);
    if(father->isroot()) now->pre=grandfa;
    else grandfa->setson(now,father->judge());
    now->setson(father,lr^1);
    father->update();now->update();
    if(grandfa!=lct) grandfa->update();
}
void splay(node *now)
{
    if(now->isroot())return;
    for(;!now->isroot();rotate(now))
    if(!now->pre->isroot())
    now->judge()==now->pre->judge()?rotate(now->pre):rotate(now);
}
node *access(node *now)
{
    node *last=lct;
    for(;now!=lct;last=now,now=now->pre)
    {
        splay(now);
        now->setson(last,1);
    }
    return last;
}
void changeroot(node *now)
{
    access(now)->rev^=1;
    splay(now);
}
void connect(node *x,node *y)
{
    changeroot(x);
    x->pre=y;
    access(x);
}
void cut(node *x,node *y)
{
    changeroot(x);
    access(y);
    splay(x);
    x->pushdown();
    x->son[1]=y->pre=lct;
    x->update();
}
int query(node *x,node *y)
{
    changeroot(x);
    node *now=access(y);
    return now->sum;
}
int main()
{
    scanf("%d%d",&a,&b);
    node *A=getnew(a);
    node *B=getnew(b);
    //连边 Link
        connect(A,B);
    //断边 Cut
        cut(A,B);
    //再连边orz Link again
        connect(A,B);
    printf("%d\n",query(A,B)); 
    return 0;
}

树状数组

#include<iostream>
#include<cstring>
using namespace std;
int lowbit(int a)
{
    return a&(-a);
}
int main()
{
    int n=2,m=1;
    int ans[m+1];
    int a[n+1],c[n+1],s[n+1];
    int o=0;
    memset(c,0,sizeof(c));
    s[0]=0;
    for(int i=1;i<=n;i++)
    {
        cin>>a[i];
        s[i]=s[i-1]+a[i];
        c[i]=s[i]-s[i-lowbit(i)];//树状数组创建前缀和优化
    }
    for(int i=1;i<=m;i++)
    {
        int q=2;
        //if(q==1)
        //{（没有更改操作）
        //    int x,y;
        //    cin>>x>>y;
        //    int j=x;
        //    while(j<=n)
        //    {
        //        c[j]+=y;
        //        j+=lowbit(j);
        //    }
        //}
        //else
        {
            int x=1,y=2;//求a[1]+a[2]的和
            int s1=0,s2=0,p=x-1;
            while(p>0)
            {
                s1+=c[p];
                p-=lowbit(p);//树状数组求和操作，用两个前缀和相减得到区间和
            }
            p=y;
            while(p>0)
            {
                s2+=c[p];
                p-=lowbit(p);
            }    
            o++;
            ans[o]=s2-s1;//存储答案
        }
    }
    for(int i=1;i<=o;i++)
        cout<<ans[i]<<endl;//输出
    return 0;
}

\\splay
#include <bits/stdc++.h>
#define ll long long
#define N 100000
using namespace std;
int sz[N], rev[N], tag[N], sum[N], ch[N][2], fa[N], val[N];
int n, m, rt, x;
void push_up(int x){
    sz[x] = sz[ch[x][0]] + sz[ch[x][1]] + 1;
    sum[x] = sum[ch[x][1]] + sum[ch[x][0]] + val[x];
}
void push_down(int x){
    if(rev[x]){
        swap(ch[x][0], ch[x][1]);
        if(ch[x][1]) rev[ch[x][1]] ^= 1;
        if(ch[x][0]) rev[ch[x][0]] ^= 1;
        rev[x] = 0;
    }
    if(tag[x]){
        if(ch[x][1]) tag[ch[x][1]] += tag[x], sum[ch[x][1]] += tag[x];
        if(ch[x][0]) tag[ch[x][0]] += tag[x], sum[ch[x][0]] += tag[x];
        tag[x] = 0;
    }
}
void rotate(int x, int &k){
    int y = fa[x], z = fa[fa[x]];
    int kind = ch[y][1] == x;
    if(y == k) k = x;
    else ch[z][ch[z][1]==y] = x;
    fa[x] = z; fa[y] = x; fa[ch[x][!kind]] = y;
    ch[y][kind] = ch[x][!kind]; ch[x][!kind] = y;
    push_up(y); push_up(x);
}
void splay(int x, int &k){
    while(x != k){
        int y = fa[x], z = fa[fa[x]];
        if(y != k) if(ch[y][1] == x ^ ch[z][1] == y) rotate(x, k);
        else rotate(y, k);
        rotate(x, k);
    }
}
int kth(int x, int k){
    push_down(x);
    int r = sz[ch[x][0]]+1;
    if(k == r) return x;
    if(k < r) return kth(ch[x][0], k);
    else return kth(ch[x][1], k-r);
}
void split(int l, int r){
    int x = kth(rt, l), y = kth(rt, r+2);
    splay(x, rt); splay(y, ch[rt][1]);
}
void rever(int l, int r){
    split(l, r);
    rev[ch[ch[rt][1]][0]] ^= 1;
}
void add(int l, int r, int v){
    split(l, r);
    tag[ch[ch[rt][1]][0]] += v;
    val[ch[ch[rt][1]][0]] += v;
    push_up(ch[ch[rt][1]][0]);
}
int build(int l, int r, int f){
    if(l > r) return 0;
    if(l == r){
        fa[l] = f;
        sz[l] = 1;
        return l;
    }
    int mid = l + r >> 1;
    ch[mid][0] = build(l, mid-1, mid);
    ch[mid][1] = build(mid+1, r, mid);
    fa[mid] = f;
    push_up(mid);
    return mid;
}
int asksum(int l, int r){
    split(l, r);
    return sum[ch[ch[rt][1]][0]];
}
int main(){
    //总共两个数
    n = 2;
    rt = build(1, n+2, 0);//建树
    for(int i = 1; i <= n; i++){
        scanf("%d", &x);
        add(i, i, x);//区间加
    }
    rever(1, n);//区间翻转
    printf("%d\n", asksum(1, n));//区间求和
    return 0;
}

\\最短代码
#include<cstdio>
std::int main(){std::int a,b;return(scanf("%d%d",&a,&b),printf("%d",a+b))&0;}