0_0_37218048_7212.cpp 0_0_37218048_7212.cpp(4) : error C3861: “scanf”: 找不到标识符 0_0_37218048_7212.cpp(6) : error C3861: “printf”: 找不到标识符 0_0_37218048_7212.cpp(6) : error C3861: “gcd”: 找不到标识符