This program is to enter the scores, get the grades, and display the result.
However, I get a fatal error LNK1120: 1 unresolved externals
Does anyone know how to solve this problem?

#include <iostream>
#include <iomanip>
using namespace std;

// Function prototype
void letter(double score, double resultNum, char grade); //recieve grade
double calc_average(double sum, double num);
char grade[10];
double score[10];

double resultNum = 0;
int i = 1; // for visual appeal
int total_times =1;
double avg = 0;
double sum = 0;
double high = 0;
double low = 100;

double jjj;

int main()
{
	do
	{
		cout << "Enter result " << i << " (or -1 if no more results) ";
		cin >> score[i];
		jjj = score[i];
		if(score[i]!=-1)
		{
			sum=sum+jjj; //save inputs before continuing
			if (jjj>high)
				high = jjj; //check for high grades

			if (jjj<low)
				low = jjj; //check for low grades

			resultNum++; //used to divide average
			
			letter(score[i], resultNum, grade[i]); //recieve grade
			i++;
			total_times = i;
		}
	}while (score[i] !=-1);

	////////////////////////////////////////////////////////
	cout << "\nThe list of the results and grades are: " << endl; 

	for ( i= 1; i < total_times; i++)

		cout << "Result " << i << ": " << score[i] << "\t  Grade: " << grade[i] << endl;
		
	//////////////////////////////////////////////////////////

	//calc_average function for beautiful clean code
	cout << "\nThe Average of the results = " << calc_average(sum,resultNum) << endl;
	cout << "The Lowest of the results = " << low << endl; 
	cout << "The Highest of the results = " << high << endl;
} 

double calc_average(double sum, double num)
{
	return (sum/num);
}

void letter(double score, double resultNum, int i)
{
	if (score<60)
	{
		cout << "Result " << resultNum << " is a U\n" << endl;
		grade[i] = 'U';
	}
	if (score>=60 && score<70)
	{
		cout << "Result " << resultNum << " is a C\n" << endl;
		grade[i] = 'C';
	}
	if (score>=70 && score<90)
	{
		cout << "Result " << resultNum << " is a B\n" << endl;
		grade[i] = 'B';
	}
	if (score>=90)
	{
		cout << "Result " << resultNum << " is a A\n" << endl;
		grade[i] = 'A';
	}
}

Edited 5 Years Ago by chuyauchi: n/a

that error means the linker cannot find some or all of the libraries it needs to do its job, you'll need to check your compiler/linker documentation and installation to figure out how to make those known.

Addition error message:

1>test.obj : error LNK2019: unresolved external symbol "void __cdecl letter(double,double,char)" (?letter@@YAXNND@Z) referenced in function _main
1>c:\users\administrator\documents\visual studio 2010\Projects\test\Debug\test.exe : fatal error LNK1120: 1 unresolved externals


========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

#include <iostream>
#include <iomanip>
using namespace std;

// Function prototype
 char grade[10];
double score[10];

double resultNum = 0;
int i = 1; // for visual appeal
int total_times =1;
double avg = 0;
double sum = 0;
double high = 0;
double low = 100;

double jjj;
double calc_average(double sum, double num)
{
    return (sum/num);
}

void letter(double score, double resultNum, int i)
{
    if (score<60)
    {
        cout << "Result " << resultNum << " is a U\n" << endl;
        grade[i] = 'U';
    }
    if (score>=60 && score<70)
    {
        cout << "Result " << resultNum << " is a C\n" << endl;
        grade[i] = 'C';
    }
    if (score>=70 && score<90)
    {
        cout << "Result " << resultNum << " is a B\n" << endl;
        grade[i] = 'B';
    }
    if (score>=90)
    {
        cout << "Result " << resultNum << " is a A\n" << endl;
        grade[i] = 'A';
    }

}


int main()
{
    do
    {
        cout << "Enter result " << i << " (or -1 if no more results) ";
        cin >> score[i];
        jjj = score[i];
        if(score[i]!=-1)
        {
            sum=sum+jjj; //save inputs before continuing
            if (jjj>high)
                high = jjj; //check for high grades

            if (jjj<low)
                low = jjj; //check for low grades

            resultNum++; //used to divide average

            letter(score[i], resultNum, grade[i]); //recieve grade
            i++;
            total_times = i;
        }
    }while (score[i] !=-1);

    ////////////////////////////////////////////////////////
    cout << "\nThe list of the results and grades are: " << endl; 

    for ( i= 1; i < total_times; i++)

        cout << "Result " << i << ": " << score[i] << "\t  Grade: " << grade[i] << endl;

    //////////////////////////////////////////////////////////

    //calc_average function for beautiful clean code
    cout << "\nThe Average of the results = " << calc_average(sum,resultNum) << endl;
    cout << "The Lowest of the results = " << low << endl; 
    cout << "The Highest of the results = " << high << endl;
        return 0;
}

Edited 3 Years Ago by Nick Evan: Fixed formatting

#include <iostream>
#include <iomanip>
using namespace std;

// Function prototype
 char grade[10];
double score[10];

double resultNum = 0;
int i = 1; // for visual appeal
int total_times =1;
double avg = 0;
double sum = 0;
double high = 0;
double low = 100;

double jjj;
double calc_average(double sum, double num)
{
    return (sum/num);
}

void letter(double score, double resultNum, int i)
{
    if (score<60)
    {
        cout << "Result " << resultNum << " is a U\n" << endl;
        grade[i] = 'U';
    }
    if (score>=60 && score<70)
    {
        cout << "Result " << resultNum << " is a C\n" << endl;
        grade[i] = 'C';
    }
    if (score>=70 && score<90)
    {
        cout << "Result " << resultNum << " is a B\n" << endl;
        grade[i] = 'B';
    }
    if (score>=90)
    {
        cout << "Result " << resultNum << " is a A\n" << endl;
        grade[i] = 'A';
    }

}


int main()
{
    do
    {
        cout << "Enter result " << i << " (or -1 if no more results) ";
        cin >> score[i];
        jjj = score[i];
        if(score[i]!=-1)
        {
            sum=sum+jjj; //save inputs before continuing
            if (jjj>high)
                high = jjj; //check for high grades

            if (jjj<low)
                low = jjj; //check for low grades

            resultNum++; //used to divide average

            letter(score[i], resultNum, i); //recieve grade
            i++;
            total_times = i;
        }
    }while (score[i] !=-1);

    ////////////////////////////////////////////////////////
    cout << "\nThe list of the results and grades are: " << endl; 

    for ( i= 1; i < total_times; i++)

        cout << "Result " << i << ": " << score[i] << "\t  Grade: " << grade[i] << endl;

    //////////////////////////////////////////////////////////

    //calc_average function for beautiful clean code
    cout << "\nThe Average of the results = " << calc_average(sum,resultNum) << endl;
    cout << "The Lowest of the results = " << low << endl; 
    cout << "The Highest of the results = " << high << endl;
    system("pause");
        return 0;
}

Edited 3 Years Ago by Nick Evan: Fixed formatting

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