resistor tool

#include <cstdio>
#include <cmath>

const int resistances[] = {0,10,22,47,100,150,200,220,270,330,470,510,680,1000,2000,2200,3300,4700,5100,6800,10000,20000,47000,51000,68000,100000,220000,300000,470000,680000,1000000};
const int rLength = sizeof(resistances)/sizeof(*resistances);
const int max = 500000;
const int min = 10000;
const float targetRatio =  28.33333333;
float ratio = 0;
float error = 0;
float bestRatio = 0;
float bestError = 999;
int bestIndex[] = {0,0,0,0};
int minIndex = 0;
int maxIndex = rLength - 1;
int r1 = 0;
int r2 = 0;


int main(int argc, char **argv)
{
    for(int i = 0; i<rLength; i++) {
        if(resistances[i] >= min) {
            minIndex = i;
            break;
        }
    }
    for(int i = 0; i<rLength; i++) {
        if(resistances[i] <= max) {
            maxIndex = i;
        }
    }
    printf("Mininum: %d Maximum: %d\n",minIndex,maxIndex);
    printf("Mininum R: %d Maximum R: %d\n",resistances[minIndex], resistances[maxIndex]);
    //Naive Calculation
    printf("Naïve Ratio Finding...");
    for(int i = minIndex; i<=maxIndex; i++){
        for(int j = minIndex; j <=maxIndex; j++) {
            //printf("i:%d\tj:%d\n",resistances[i],resistances[j]);
            ratio = float(resistances[j]) / float(resistances[i]);
            //printf("%f\n",ratio);
            error = std::fabs(ratio - targetRatio);
            if(error < bestError) {
                bestError = error;
                bestIndex[0] = j;
                bestIndex[1] = i;
                bestRatio = ratio;
            }
        }
    }
    printf("Naïve Results:\nBest Error:\t%f\nBest Ratio:\t%f\nBest Resistances:\t%d Ω\t%d Ω\n\n",bestError,bestRatio,resistances[bestIndex[0]],resistances[bestIndex[1]]);
    printf("Series Ratio Finding\n");
    bestError = 999.0;
    for(int i = 0; i<rLength; i++) {
        for(int j = 0; j<rLength; j++) {
            for(int k = 0; k<rLength; k++) {
                for(int l = 0; l<rLength; l++) {
                    r1 = resistances[i] + resistances[j];
                    r2 = resistances[k] + resistances[l];
                    if(r1 >= min && r1 <= max && r2 >= min && r2 <= max){
                        ratio = float(r1) / float(r2);
                        //printf("r %f\n",ratio);
                        //printf("%f\n",ratio);
                        error = std::fabs(ratio - targetRatio);
                        if(error < bestError) {
                            bestError = error;
                            printf("%f ",error);
                            bestIndex[0] = i;
                            bestIndex[1] = j;
                            bestIndex[2] = k;
                            bestIndex[3] = l;
                            bestRatio = ratio;
                        }
                    }
                }
            }
        }
    }
    printf("Series Results:\nBest Error:\t%f (%f%%)\nBest Ratio:\t%f\nBest Resistances:\t%d Ω\t%d Ω\t%d Ω\t%d Ω\n\n",bestError,100.0*bestError/targetRatio,bestRatio,resistances[bestIndex[0]],resistances[bestIndex[1]],resistances[bestIndex[2]],resistances[bestIndex[3]]);
    printf("Parallel Ratio Finding\n");
    float conductances[rLength] = {};
    for(int i = 0; i<rLength; i++) {
        conductances[i] = 1.0f / (float) resistances[i];
        printf("%f ",conductances[i]);
    }
    printf("\n");
    bestError = 999.0;
    for(int i = 0; i<rLength; i++) {
        for(int j = 0; j<rLength; j++) {
            for(int k = 0; k<rLength; k++) {
                for(int l = 0; l<rLength; l++) {
                    float c1 = conductances[i] + conductances[j];
                    float c2 = conductances[k] + conductances[l];
                    r1 = (int) round(1.0 / c1);
                    r2 = (int) round(1.0 / c2);
                    if(r1 >= min && r1 <= max && r2 >= min && r2 <= max){
                        ratio = float(r1) / float(r2);
                        //printf("r %f\n",ratio);
                        //printf("%f\n",ratio);
                        error = std::fabs(ratio - targetRatio);
                        if(error < bestError) {
                            bestError = error;
                            bestIndex[0] = i;
                            bestIndex[1] = j;
                            bestIndex[2] = k;
                            bestIndex[3] = l;
                            bestRatio = ratio;
                        }
                    }
                }
            }
        }
    }
    printf("Parallel Results:\nBest Error:\t%f (%f%%)\nBest Ratio:\t%f\nBest Resistances:\t%d Ω\t%d Ω\t%d Ω\t%d Ω\n\n",bestError,100.0*bestError/targetRatio,bestRatio,resistances[bestIndex[0]],resistances[bestIndex[1]],resistances[bestIndex[2]],resistances[bestIndex[3]]);
}