xcode在新建新的工程的时候会默认生成一份代码，例如新建一个c++工程，其初始的代码如下:
#include <iostream> int main(int argc, const char * argv[]) { // insert code here... std::cout << "Hello, World! "; return 0; }
这本无可厚非，当我们第一次用c++的时候非常友好的代码。Hello World! 只是当写算法题需要大量新建工程时，我们可能希望面对的不是这样一份几乎没用的代码，我们希望的是能够已经写了足够多的库文件或者一些初始注释
啥的。因此此时我们就需要来修改这个初始的文件。
我们找到这个文件的位置: /Applications/Xcode.app/Contents/Developer/Library/Xcode/Templates/Project Templates/Mac/Application/Command Line Tool.xctemplate/TemplateInfo.plist
语言类似html风格，我们找到我们需要修改的地方进行修改就好了。主要注意的是它用的是html的语法，因此例如 < > " & 等字符需要转义 例如< 变成> 等等。
最后说一下，上面的几个//的注释不在这个文件里修改。不过也在附近的文件里。如果你觉得看着这个初始的注释信息不顺眼也可以自己去探寻修改一下。
以及xcode更新的时候这个文件可能又会变成初始，因此改完之后最好备份一下。就酱~
另附我修改后的源文件:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Kind</key>
<string>Xcode.Xcode3.ProjectTemplateUnitKind</string>
<key>Identifier</key>
<string>com.apple.dt.unit.commandLineTool</string>
<key>Ancestors</key>
<array>
<string>com.apple.dt.unit.base</string>
<string>com.apple.dt.unit.osxBase</string>
</array>
<key>Concrete</key>
<true/>
<key>SortOrder</key>
<integer>50</integer>
<key>Description</key>
<string>This template creates a command-line tool.</string>
<key>Targets</key>
<array>
<dict>
<key>ProductType</key>
<string>com.apple.product-type.tool</string>
<key>TargetIdentifier</key>
<string>com.apple.dt.commandLineToolTarget</string>
<key>BuildPhases</key>
<array>
<dict>
<key>Class</key>
<string>Sources</string>
</dict>
<dict>
<key>Class</key>
<string>Frameworks</string>
</dict>
<dict>
<key>Class</key>
<string>CopyFiles</string>
<key>DstPath</key>
<string>/usr/share/man/man1/</string>
<key>DstSubfolderSpec</key>
<string>0</string>
<key>RunOnlyForDeploymentPostprocessing</key>
<string>YES</string>
</dict>
</array>
</dict>
</array>
<key>Options</key>
<array>
<dict>
<key>Identifier</key>
<string>commandLineType</string>
<key>Name</key>
<string>Language:</string>
<key>Description</key>
<string>The primary implementation language for the command-line tool</string>
<key>Default</key>
<string>Swift</string>
<key>Type</key>
<string>popup</string>
<key>Values</key>
<array>
<string>Swift</string>
<string>Objective-C</string>
<string>C++</string>
<string>C</string>
</array>
<key>Units</key>
<dict>
<key>C</key>
<dict>
<key>Nodes</key>
<array>
<string>main.c:comments</string>
<string>main.c:include</string>
<string>main.c:main:content</string>
</array>
<key>Definitions</key>
<dict>
<key>main.c:include</key>
<string>#include <stdio.h>
</string>
<key>main.c:main:content</key>
<string>// insert code here...
printf("Hello, World!
");
return 0;
</string>
</dict>
</dict>
<key>C++</key>
<dict>
<key>Nodes</key>
<array>
<string>main.cpp:comments</string>
<string>main.cpp:include</string>
<string>main.cpp:main:content</string>
</array>
<key>Definitions</key>
<dict>
<key>main.cpp:include</key>
<string>#include <iostream>
#include <cstdio>
#include <cstring>
#include <string>
#include <map>
#include <iostream>
#include <cmath>
#include <vector>
#include <set>
#include <algorithm>
#include <queue>
typedef long long ll;
#define rep(i,a,b) for (int i = (a); i <= (b); ++i)
#define rep2(i,a,b) for (int i = (a); i >= (b); --i)
using namespace std;
const int N = 10010;
int ans, n , m, a[N];
</string>
<key>main.cpp:main:content</key>
<string>
cin >> n >> m;
rep (i, 1, n){
scanf("%d",&a[i]);
}
ans = 0;
cout << ans << endl;
</string>
</dict>
</dict>
<key>Objective-C</key>
<dict>
<key>Nodes</key>
<array>
<string>main.m:comments</string>
<string>main.m:include</string>
<string>main.m:main:content</string>
</array>
<key>Definitions</key>
<dict>
<key>main.m:include</key>
<string>#import <Foundation/Foundation.h>
</string>
<key>main.m:main:content</key>
<string>@autoreleasepool {
// insert code here...
NSLog(@"Hello, World!");
}
return 0;
</string>
</dict>
</dict>
<key>Swift</key>
<dict>
<key>Project</key>
<dict>
<key>Configurations</key>
<dict>
<key>Debug</key>
<dict>
<key>SWIFT_OPTIMIZATION_LEVEL</key>
<string>-Onone</string>
</dict>
</dict>
</dict>
<key>Targets</key>
<array>
<dict>
<key>SharedSettings</key>
<dict>
<key>SWIFT_VERSION</key>
<string>___DEFAULTTOOLCHAINSWIFTVERSION___</string>
</dict>
</dict>
</array>
<key>Nodes</key>
<array>
<string>main.swift:comments</string>
<string>main.swift:include</string>
<string>main.swift:main:content</string>
</array>
<key>Definitions</key>
<dict>
<key>main.swift:include</key>
<string>import Foundation
</string>
<key>main.swift:main</key>
<dict>
<key>Beginning</key>
<string></string>
<key>End</key>
<string></string>
</dict>
<key>main.swift:main:content</key>
<string>print("Hello, World!")
</string>
</dict>
</dict>
</dict>
</dict>
</array>
<key>Definitions</key>
<dict>
<key>*:main</key>
<dict>
<key>Beginning</key>
<string>int main() {</string>
<key>End</key>
<string>}</string>
<key>Indent</key>
<integer>1</integer>
</dict>
</dict>
</dict>
</plist>