src.cpp: In function 'int main()':
src.cpp:7:16: error: redeclaration of 'std::ifstream f1'
ifstream f1("SOMAYMAN.INP");
^
src.cpp:6:14: note: 'std::ifstream f1' previously declared here
ifstream f1("SOMAYMAN.INP");
^
src.cpp:21:9: error: 'f2' was not declared in this scope
f2<<dem<<endl;
^