Error C4430, error C2065

#include "stdafx.h"
#include <iostream>
#include "diophantine.h"
using namespace std;
 
void main() {
 
   CDiophantine dp(1,2,3,4,30);
 
   int ans;
   ans = dp.Solve();
   if (ans == -1) {
      cout << "No solution found." << endl;
   } else {
      gene gn = dp.GetGene(ans);
 
      cout << "The solution set to a+2b+3c+4d=30 is:\n";
      cout << "a = " << gn.alleles[0] << "." << endl;
      cout << "b = " << gn.alleles[1] << "." << endl;
      cout << "c = " << gn.alleles[2] << "." << endl;
      cout << "d = " << gn.alleles[3] << "." << endl;
   }
}

#include "stdafx.h"
#include <iostream>
#include <stdlib.h>
#include <time.h>
 
#define MAXPOP  25
 
struct gene {
    int alleles[4];
    int fitness;
    float likelihood;
    operator==(gene gn) {
        for (int i=0;i<4;i++) {
            if (gn.alleles[i] != alleles[i]) return false;
        }
 
        return true;
    }
};
 
class CDiophantine {
    public:
        CDiophantine(int, int, int, int, int);// Constructor with coefficients for a,b,c,d.
        int Solve();// Solve the equation.
        
        // Returns a given gene.
        gene GetGene(int i) { return population[i];}
 
    protected:
        int ca,cb,cc,cd;// The coefficients.
        int result;
        gene population[MAXPOP];// Population.
 
        int Fitness(gene &);// Fitness function.
        void GenerateLikelihoods(); // Generate likelihoods.
        float MultInv();// Creates the multiplicative inverse.
        int CreateFitnesses();
        void CreateNewPopulation();
        int GetIndex(float val);
 
        gene Breed(int p1, int p2);
 
};
 
CDiophantine::CDiophantine(int a, int b, int c, int d, int res) : ca(a), cb(b), cc(c), cd(d), result(res) {}
 
int CDiophantine::Solve() {
    int fitness = -1;
 
    // Generate initial population.
    srand((unsigned)time(NULL));
 
    for(int i=0;i<MAXPOP;i++) {// Fill the population with numbers between
        for (int j=0;j<4;j++) {// 0 and the result.
            population[i].alleles[j] = rand() % (result + 1);
        }
    }
 
    if (fitness = CreateFitnesses()) {
        return fitness;
    }
 
    int iterations = 0;// Keep record of the iterations.
    while (fitness != 0 || iterations < 50) {// Repeat until solution found, or over 50 iterations.
        GenerateLikelihoods();// Create the likelihoods.
        CreateNewPopulation();
        if (fitness = CreateFitnesses()) {
            return fitness;
        }
        
        iterations++;
    }
 
    return -1;
}
 
int CDiophantine::Fitness(gene &gn) {
    int total = ca * gn.alleles[0] + cb * gn.alleles[1] + cc * gn.alleles[2] + cd * gn.alleles[3];
 
    return gn.fitness = abs(total - result);
}
 
int CDiophantine::CreateFitnesses() {
    float avgfit = 0;
    int fitness = 0;
    for(int i=0;i<MAXPOP;i++) {
        fitness = Fitness(population[i]);
        avgfit += fitness;
        if (fitness == 0) {
            return i;
        }
    }
    
    return 0;
}
 
float CDiophantine::MultInv() {
    float sum = 0;
 
    for(int i=0;i<MAXPOP;i++) {
        sum += 1/((float)population[i].fitness);
    }
 
    return sum;
}
 
void CDiophantine::GenerateLikelihoods() {
    float multinv = MultInv();
 
    float last = 0;
    for(int i=0;i<MAXPOP;i++) {
        population[i].likelihood = last = last + ((1/((float)population[i].fitness) / multinv) * 100);
    }
}
 
int CDiophantine::GetIndex(float val) {
    float last = 0;
    for(int i=0;i<MAXPOP;i++) {
        if (last <= val && val <= population[i].likelihood) return i;
        else last = population[i].likelihood;
    }
    
    return 4;
}
 
gene CDiophantine::Breed(int p1, int p2) {
    int crossover = rand() % 3+1;// Create the crossover point (not first).
    int first = rand() % 100;// Which parent comes first?
 
    gene child = population[p1];// Child is all first parent initially.
 
    int initial = 0, final = 3;// The crossover boundaries.
    if (first < 50) initial = crossover;    // If first parent first. start from crossover.
    else final = crossover+1;// Else end at crossover.
 
    for(int i=initial;i<final;i++) {// Crossover!
        child.alleles[i] = population[p2].alleles[i];
        if (rand() % 101 < 5) child.alleles[i] = rand() % (result + 1);
    }
 
    return child;// Return the kid...
}
 
void CDiophantine::CreateNewPopulation() {
    gene temppop[MAXPOP];
 
    for(int i=0;i<MAXPOP;i++) {
        int parent1 = 0, parent2 = 0, iterations = 0;
        while(parent1 == parent2 || population[parent1] == population[parent2]) {
            parent1 = GetIndex((float)(rand() % 101));
            parent2 = GetIndex((float)(rand() % 101));
            if (++iterations > 25) break;
        }
        
        temppop[i] = Breed(parent1, parent2);// Create a child.
    }
 
    for(i=0;i<MAXPOP;i++) population[i] = temppop[i];
}