#include<iostream> using namespace std; void baron(int a) { printf("%d",a); } int main() { long long a; cin>>a; baron(a); return 0; }

#include<iostream> using namespace std; int main() { int a; cin>>a; cout<<a; return 0; }

#include <iostream> using namespace std; const int N=4000000; bool del[N+10]; void sd(int n){ del[0]=1; del[1]=1; for(int i=2;ii<=n;i++){ if(del[i]==0){ for(int j=2i;j<=n;j+=i){ del[j]=1; } } } } int main(){ int n,cnt; cin>>n; sd(n); for(int i=2;i<=n;i++){ if(del[i]==0){ cnt++; } } cout<<n; return 0; }

导入头文件： ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 固定写法 #include 头文件名称 <iostream> 创建命名空间： ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 固定写法（使用） using 固定写法（命名空间）namespace 命名空间名称 std 主函数： ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 序号 注意 ① 任何 C++ 程序的主函数均是 main() 函数 ② 任何 C++ 程序有且仅有一个 main() 函数 ③ 任何 C++ 程序 main() 函数均是唯一入口 固定写法（程序入口） int main() { 固定写法（程序出口） return 0; } 程序主体： ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 结合： ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 拜拜~~~

简单的输入输出操作！ a=input() print(a)

喜爱装好吧,😁 #include <iostream> #include <string> #include <vector> typedef long long Int; typedef stdvector<Int> Nat; Nat fromInt(Int x) { Nat n{}; for (; x; x /= 10) n.push_back(x % 10); return n; } Nat fromString(stdstring s) { Nat n{}; for (Int i = (Int)s.size() - 1; i >= 0; i--) n.push_back(s[i] - '0'); while (n.size() && !n.back()) n.pop_back(); return n; } stdstring toString(Nat n) { if (!n.size()) return "0"; stdstring s = ""; for (Int i = (Int)n.size() - 1; i >= 0; i--) { s += n[i] + '0'; } return s; } int main() { stdstring s1; stdcin>>s1; Nat n1=fromString(s1); stdcout<<toString(n1)<<stdendl;}

#include<bits/stdc++.h> using namespace std; int main() { int a; cin>>a; cout<<a; return 0; }

#include <iostream> using namespace std; int main() { int a; cin >> a; cout << a; return 0; }

#include <iostream> using namespace std; int main(){ int a; cin>>a; cout<<a; }

方法一： #include<bits/stdc++.h> using namespace std; int s; int main(){ cin>>s; cout<<s; return 0; } 方法二（输入的数大小不限）： #include<bits/stdc++.h> using namespace std; string s; int main(){ cin>>s; cout<<s; return 0; }

C++的用户可以看一下。 Python的用户有兴趣也可以进来看一下。 #include <iostream> using namespace std; int main() { int a; cin>>a; cout <<a; return 0; }

A7814.变量输入输出 难度：入门 来源：官方 AC代码（C/C++）: ※温馨提示：提交时需将auto修改为int哦~ 没有注释，自行学习。 by：ጿ ኈ ቼ ዽ ጿ ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 你的点赞和关注就是我更新题解的最大动力！ ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ -----------------------------点个赞吧 ↓ ！-----------------------------

    ∙    i  提醒 启动原神      ∙    ×  错误 卸载原神      ∙    √  正确 下载原神      ∙    √  正确 原神，启动！！！   % w, h, fillcol, bordercol \newcommand\BorderRect[4]{ \color{#3}\rule{#1}{#2}\kern{-#1} \color{#4}\rule{1px}{#2}\kern{-0.5px} \rule{#1}{0px}\rule{0.5px}{#2}\kern{-0.5px} \kern{-#1}\rule[#2]{#1}{0px} } % w, h, title, subtitle, fillcol, iconch ,iconcol \newcommand\BasicInfoBarFather[7]{ \BorderRect{#1}{#2}{#5}{ghostwhite} \kern{-#1} \raisebox{#2}{ \raisebox{-26pt}{ \color{black}\kern{-4px} \raisebox{7px}{ \color{#7}\Huge{∙}\kern{-1px} } \raisebox{10.6px}{ \kern{-20.2px} \color{white}\scriptsize\textbf{#6} } \kern{-7px}\footnotesize \raisebox{10.2px}{\textbf{\textsf{#3}}}\kern{2px} \raisebox{10.2px}{\textsf{#4}} } } } \def\BasicInfoBarColorFill{#F4F4F4}\def\BasicInfoBarColorIcon{#0078D4} \def\BasicWarnBarColorFill{#FFF4CE}\def\BasicWarnBarColorIcon{#9D5D00} \def\BasicOkBarColorFill{#DFF6DD}\def\BasicOkBarColorIcon{#0F7B0F} \def\BasicErrBarColorFill{#FDE7E9}\def\BasicErrBarColorIcon{#C42B1C} \newcommand\BasicInfoBar[4]{ \BasicInfoBarFather{#1}{#2}{#3}{#4} {\BasicInfoBarColorFill}{i}{\BasicInfoBarColorIcon} } \newcommand\BasicWarnBar[4]{ \BasicInfoBarFather{#1}{#2}{#3}{#4} {\BasicWarnBarColorFill} {\tiny\kern{-1.3px}\raisebox{0.8px}{⚠}} {\BasicWarnBarColorIcon} } \newcommand\BasicOkBar[4]{ \BasicInfoBarFather{#1}{#2}{#3}{#4} {\BasicOkBarColorFill} {\tiny\kern{-2px}\raisebox{0.8px}{√}} {\BasicOkBarColorIcon} } \newcommand\BasicErrBar[4]{ \BasicInfoBarFather{#1}{#2}{#3}{#4} {\BasicErrBarColorFill} {\kern{-2px}\raisebox{0.7px}{×}} {\BasicErrBarColorIcon} } \BasicInfoBar{200px}{26px}{提醒}{启动原神}\\ \BasicErrBar{200px}{26px}{错误}{卸载原神}\\ \BasicOkBar{200px}{26px}{正确}{下载原神}\\ \BasicOkBar{200px}{26px}{正确}{原神，启动！！！}\\     ∙    i  提醒 启动原神       ∙    ×   错误 卸载原神       ∙    √   正确 下载原神       ∙    √   正确 原神，启动！！！    原神，启动！！！\color{red}\Huge {原神，启动！！！} 原神，启动！！！

#include <iostream> using namespace std; int main(){ int a; cin >> a; cout << a; }

#include <iostream> using namespace std; int main() { int a; cin>>a; cout<<a; return 0; }

就那么简单

直接上代码：