Remove uses of implicit namespace std
Fixed via:
sed -i '/using namespace std/{N;d}' src/*.cpp
sed -i 's/ string/ std::string/g' src/*.cpp
sed -i 's/(string/(std::string/g' src/*.cpp
sed -i 's/\[string/\[std::string/g' src/*.cpp
sed -i 's/^string/std::string/g' src/*.cpp
sed -i 's/ ifstream/ std::ifstream/g' src/*.cpp
sed -i 's/ istringstream/ std::istringstream/g' src/*.cpp
sed -i 's/ ostringstream/ std::ostringstream/g' src/*.cpp
sed -i 's/ max(/ std::max(/g' src/*.cpp
sed -i 's/ min(/ std::min(/g' src/*.cpp
sed -i 's/ endl/ std::endl/g' src/*.cpp