Mac上的C ++：鏈接器命令失敗，退出代碼為1（使用-v查看調用）

Question

Ld /Users/rahulshrestha/Library/Developer/Xcode/DerivedData/101-bdjjlwlibkuaakgjcxqoslsirofh/Build/Products/Debug/101 normal x86_64
    cd /Users/rahulshrestha/Dropbox/C++/101
    export MACOSX_DEPLOYMENT_TARGET=10.9
    /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -arch x86_64 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk -L/Users/rahulshrestha/Library/Developer/Xcode/DerivedData/101-bdjjlwlibkuaakgjcxqoslsirofh/Build/Products/Debug -F/Users/rahulshrestha/Library/Developer/Xcode/DerivedData/101-bdjjlwlibkuaakgjcxqoslsirofh/Build/Products/Debug -filelist /Users/rahulshrestha/Library/Developer/Xcode/DerivedData/101-bdjjlwlibkuaakgjcxqoslsirofh/Build/Intermediates/101.build/Debug/101.build/Objects-normal/x86_64/101.LinkFileList -mmacosx-version-min=10.9 -stdlib=libc++ -Xlinker -dependency_info -Xlinker /Users/rahulshrestha/Library/Developer/Xcode/DerivedData/101-bdjjlwlibkuaakgjcxqoslsirofh/Build/Intermediates/101.build/Debug/101.build/Objects-normal/x86_64/101_dependency_info.dat -o /Users/rahulshrestha/Library/Developer/Xcode/DerivedData/101-bdjjlwlibkuaakgjcxqoslsirofh/Build/Products/Debug/101

duplicate symbol _main in:
    /Users/rahulshrestha/Library/Developer/Xcode/DerivedData/101-bdjjlwlibkuaakgjcxqoslsirofh/Build/Intermediates/101.build/Debug/101.build/Objects-normal/x86_64/main.o
    /Users/rahulshrestha/Library/Developer/Xcode/DerivedData/101-bdjjlwlibkuaakgjcxqoslsirofh/Build/Intermediates/101.build/Debug/101.build/Objects-normal/x86_64/praca.o
ld: 1 duplicate symbol for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

#include <iostream>
using namespace std;

int main() {
    double radius, circumference, area; // Declare 3 floating-point variables
    const double PI = 3.14159265;       // Declare and define PI

cout << "Enter the radius: ";  // Prompting message
cin >> radius;                 // Read input into variable radius

// Compute area and circumference
area = radius * radius * PI;
circumference = 2.0 * radius * PI;

// Print the results
cout << "The radius is: " << radius << endl;
cout << "The area is: " << area << endl;
cout << "The circumference is: " << circumference << endl;

return 0;
}

Answer 1

您只能擁有一個main（）-您決定需要保留哪一個以及需要刪除哪一個。 使用main（）方法僅保留一頁。

Answer 2

該錯誤消息告訴您您需要了解的所有內容-您有兩個主電源-一個在main.cpp中，一個在praca.cpp中。只能有1個主方法。

Answer 3

該線程上的其他人已經在這里指出了問題。 我將嘗試給出上下文。

編譯程序時，C ++編譯器會在目標文件中尋找其定義的主要功能，並將其編譯為調用程序的入口點。

如您的錯誤所示，編譯器在praca.o（praca.cpp？）中找到2個主要函數定義，而在main.o（main.cpp？）中找到另一個主函數定義。

因此，您必須在main.cpp或praca.cpp中選擇main並刪除另一個。