using system;namespace riya{class riya1{public static void Main(string[] args){console.writeline("hi");console.readline();}}}
Standard input is empty
prog.cs(1,7): error CS0246: The type or namespace name `system' could not be found. Are you missing a using directive or an assembly reference? Compilation failed: 1 error(s), 0 warnings
Standard output is empty
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