0_0_13810679_6888.cpp:17:9: error: stray '\' in program double s=(W*H)\num; ^ 0_0_13810679_6888.cpp: In function 'int main()': 0_0_13810679_6888.cpp:17:24: error: expected ',' or ';' before 'num' double s=(W*H)\num; ^