How to get rid of this error: "MSVCRTD.lib (crtexe.obj): error LNK2019: unresolved external _main character referenced by the ___tmainCRTStartup function"

I help a friend with her C ++, but honestly, we need a lot of help.

Why do we always get this error: "MSVCRTD.lib (crtexe.obj): error LNK2019: unresolved external character specified in the __tmainCRTStartup function"

Code below:

//Maria Delgado (1013725) - Coursework 2 - Program Conducting timber component structural design #include<iostream> #include<iomanip> #include<cmath> #include<fstream> #include<string> using namespace std; //Variables for Strength Properties in (N/mm2) //fmk=Bending //fc90k=Compression Perpendicular //fvk=Shear //Calculating Member Size Factor: void memberSizeFactor(double chosenDepth) { if (chosenDepth<150) kH=pow(150/chosenDepth,0.2); else cout<<"Please input a depth less than 150mm"<<endl; } //Error message for all negative values entered double errorNeg() { float value=-1; while (value<0) { cout<<"You have entered a negative value. This variable cannot take negative values. Please input positive values!"; cin>>value; cout<<endl; } return value; } //Beam Member Class class beamMember { private: double chosenLength; double chosenWidth; double chosenDepth; double chosenBearingLength; double serviceClassAbility; string strengthClass; public: beamMember() { chosenLength=chosenWidth=chosenDepth=chosenBearingLength=serviceClassAbility=0; strengthClass=""; } void beamDimensionsData() { cout<<"The following dimensions need to be input into the program:"<<endl; cout<<"What is the desired beam LENGTH in millimeters?"; cin>>chosenLength; if(chosenLength<0) chosenLength=errorNeg(); cout<<"What is the desired beam WIDTH in millimeters?"; cin>>chosenWidth; if(chosenWidth<0) chosenWidth=errorNeg(); cout<<"What is the desired beam DEPTH in millimeters?"; cin>>chosenDepth; if(chosenDepth<0) chosenDepth=errorNeg(); cout<<"What is the desired beam BEARING LENGTH in millimeters?"; cin>>chosenBearingLength; if(chosenBearingLength<0) chosenBearingLength = errorNeg(); cout<<"Please insert a strength class of timber egC12 to C50:"; cin>>strengthClass; cout<<endl<<"Please choose a service class ability for member ie 1 or 2 or 3:"; cin>>serviceClassAbility; cout<<endl; } //***************************CALCULATE OVERALL DESIGN LOAD************************************************************ double load(beamMember designBeam) { cout<<"Under these circumstances, the beam will be adequate to support a slab."<<endl<<endl; double qK; double gK; double span; cout<<"Please input the total live load in kN/m2:"; cin>>qK; cout<<endl; if (qK<0) qK=errorNeg(); qK=qK*gammaQ; cout<<"Please input the total dead load in kN/m2:"; cin>>gK; if (gK<0) gK=errorNeg(); gK=gK*gammaG; cout<<"Enter the span between the beams in millimeters:"; cin>>span; while(span<0) span=errorNeg(); cout<<endl; span=span*(qK+gK)*chosenLength/10e2; cout<<"Point load:"<<span<<"N"<<endl<<endl; return span; } //***********************************CHECKING BENDING STRESS********************************************************* void checkBendingStress(beamMember designBeam, double force) { cout<<"Bending Stress Check:"<<endl; double bendingMoment; double secondMomentofArea; double designBendingStress; double actualBendingStress; bendingMoment=force*chosenLength/8; cout<<"Maximum bending moment is "<<bendingMoment<<"Nmm"<<endl; secondMomentofArea=chosenWidth*pow(chosenDepth,3)/12; designBendingStress=kH*kSYS*kMOD*matrix[0]/gammaM; actualBendingStress=(bendingMoment*chosenDepth/2)/secondMomentofArea; cout<<"Maximum permissibile stress:"<<designBendingStress<<"N/mm2"<<endl; cout<<"The actual stress that the beam is subject to:"<<actualBendingStress<<"N/mm2"<<endl; if(actualBendingStress<=designBendingStress) cout<<"Beam bending stress check successful!"<<endl<<endl; else cout<<"Beam bending stress check unnsuccessful!"<<endl<<endl; } //***********************************CHECKING SHEAR STRESS********************************************************* void checkShearStress(beamMember designBeam, double force) { cout<<"Shear Stress Check:"<<endl; double designShearingStress; double actualShearingStress; designShearingStress=matrix[5]*kMOD*kSYS/gammaM; actualShearingStress=(1.5*force/2)/(chosenWidth)/(chosenDepth); cout<<"Maximum permissible shear stress:"<<designShearingStress<<"N/mm2"<<endl; cout<<"Shear stress that the supports are subjected to:"<<actualShearingStress<<"N/mm2"<<endl; if(actualShearingStress<=designShearingStress) cout<<"Beam shear stress check successful!"<<endl<<endl; else cout<<"Beam shear stress check unsucessful!"<<endl<<endl; } //********************************CHECKING BEARING STRESS*********************************************************** void checkBearingStress(beamMember designBeam, double force) { double kc90; double designBearingStress; double actualBearingStress; actualBearingStress=force/2/chosenWidth/chosenBearingLength; cout<<"Bearing Stress that the beam is subjected to:"<<actualBearingStress<<"N/mm2"<<endl; designBearingStress=matrix[4]*kMOD*kSYS/gammaM; cout<<"Maximum permissible bearing stress:"<<designBearingStress<<"N/mm2"<<endl; kc90=(2.38-chosenBearingLength/250)*(1+chosenDepth/12/chosenBearingLength); cout<<"Constant, kc90 is "<<kc90<<endl; cout<<"Factored design bearing stress is "<<kc90*designBearingStress<<endl; if (actualBearingStress<=designBearingStress) cout<<"Beam bearing stress check successful!"<<endl<<endl; else cout<<"Beam bearing stress check unsuccessful!"<<endl<<endl; } //********************************CHECKING LATERAL TORSIONAL STABILITY************************************************** void checkLateralTorsionalStability(beamMember designBeam, double force) { cout<<"Lateral Torsional Stability Check:"<<endl; double bendingMoment; double secondMomentofArea; double designBendingStress; double actualBendingStress; bendingMoment=force*chosenLength/8; cout<<"Maximum bending moment is "<<bendingMoment<<"Nmm"<<endl; secondMomentofArea=chosenWidth*pow(chosenDepth,3)/12; designBendingStress=kH*kSYS*kMOD*matrix[0]/gammaM; actualBendingStress=(bendingMoment*chosenDepth/2)/secondMomentofArea; cout<<"Maximum permissibile stress:"<<designBendingStress<<"N/mm2"<<endl; cout<<"The actual stress that the beam is subject to:"<<actualBendingStress<<"N/mm2"<<endl; if(actualBendingStress<=designBendingStress) cout<<"Beam Lateral Torsional Stability check successful!"<<endl<<endl; else cout<<"Beam Lateral Tosional Stability check unnsuccessful!"<<endl<<endl; } //*************************************FUNCTION FOR STRENGTH CLASS DATA FILE********************************************** void strengthClassData(string classStrength, double serviceClass) { string data; ifstream file; file.open("strengthclassdata.txt"); file>>data; while(file&&data!=classStrength) { file>>data; } for(int i=0;i<=5;i++) file>>matrix[i]; file.close(); } //Welcome Message for Program void welcome() { cout<<"The following is Yadhuvamshi Rajamani program"<<endl <<"that conducts timber component structural design"<<endl <<"according to EC5. Specifically, it is a limit state"<<endl <<"design program that compares design actions with design strengths."<<endl; } //******************************BEAM START UP***************************************************************************** void beamStartUp() { beamMember designBeam; double force; designBeam.beamDimensionsData(); force=load(designBeam); checkBendingStress(designBeam,force); checkShearStress(designBeam,force); checkBearingStress(designBeam,force); checkLateralTorsionalStability(designBeam,force); } int main() { welcome(); char startKey; cout<<"Please select 1 to start the beam test program or 2 to exit the program, followed by enter!"; cin>>startKey; cout<<endl; while(startKey!='2') { switch(startKey) { case '2': return 1; case '1': beamStartUp(); break; } cout<<"Please select 1 to start the beam test program or 2 to exit the program, followed by enter!"; cin>>startKey; cout<<endl; } return 1; } }; ` 
+7
source share
2 answers

The int main() function must be outside your class definition. You will want to instantiate the class and use it to call the welcome and beamStartUp functions.

+8
source
+5
source

All Articles