Task: Aliquot sequence classifications

C: #include<stdlib.h>
#include<string.h>
#include<stdio.h>

unsigned long long bruteForceProperDivisorSum(unsigned long long n){
	unsigned long long i,sum = 0;
	
	for(i=1;i<(n+1)/2;i++)
		if(n%i==0 && n!=i)
			sum += i;
		
	return sum;
}

void printSeries(unsigned long long* arr,int size,char* type){
	int i;
	
	printf("\nInteger : %llu, Type : %s, Series : ",arr[0],type);
	
	for(i=0;i<size-1;i++)
		printf("%llu, ",arr[i]);
	printf("%llu",arr[i]);
}

void aliquotClassifier(unsigned long long n){
	unsigned long long arr[16];
	int i,j;
	
	arr[0] = n;
	
	for(i=1;i<16;i++){
		arr[i] = bruteForceProperDivisorSum(arr[i-1]);
		
		if(arr[i]==0||arr[i]==n||(arr[i]==arr[i-1] && arr[i]!=n)){
			printSeries(arr,i+1,(arr[i]==0)?"Terminating":(arr[i]==n && i==1)?"Perfect":(arr[i]==n && i==2)?"Amicable":(arr[i]==arr[i-1] && arr[i]!=n)?"Aspiring":"Sociable");
			return;
		}
		
		for(j=1;j<i;j++){
			if(arr[j]==arr[i]){
				printSeries(arr,i+1,"Cyclic");
				return;
			}
		}
	}
	
	printSeries(arr,i+1,"Non-Terminating");
}

void processFile(char* fileName){
	FILE* fp = fopen(fileName,"r");
	char str[21];
	
	while(fgets(str,21,fp)!=NULL)
		aliquotClassifier(strtoull(str,(char**)NULL,10));
	
	fclose(fp);
}

int main(int argC,char* argV[])
{
    if(argC!=2)
		printf("Usage : %s <positive integer>",argV[0]);
	else{
		if(strchr(argV[1],'.')!=NULL)
			processFile(argV[1]);
		else
			aliquotClassifier(strtoull(argV[1],(char**)NULL,10));
	}
	return 0;
}


C++: #include <cstdint>
#include <iostream>
#include <string>

using integer = uint64_t;


integer divisor_sum(integer n) {
    integer total = 1, power = 2;
    
    for (; n % 2 == 0; power *= 2, n /= 2)
        total += power;
    
    for (integer p = 3; p * p <= n; p += 2) {
        integer sum = 1;
        for (power = p; n % p == 0; power *= p, n /= p)
            sum += power;
        total *= sum;
    }
    
    if (n > 1)
        total *= n + 1;
    return total;
}


void classify_aliquot_sequence(integer n) {
    constexpr int limit = 16;
    integer terms[limit];
    terms[0] = n;
    std::string classification("non-terminating");
    int length = 1;
    for (int i = 1; i < limit; ++i) {
        ++length;
        terms[i] = divisor_sum(terms[i - 1]) - terms[i - 1];
        if (terms[i] == n) {
            classification =
                (i == 1 ? "perfect" : (i == 2 ? "amicable" : "sociable"));
            break;
        }
        int j = 1;
        for (; j < i; ++j) {
            if (terms[i] == terms[i - j])
                break;
        }
        if (j < i) {
            classification = (j == 1 ? "aspiring" : "cyclic");
            break;
        }
        if (terms[i] == 0) {
            classification = "terminating";
            break;
        }
    }
    std::cout << n << ": " << classification << ", sequence: " << terms[0];
    for (int i = 1; i < length && terms[i] != terms[i - 1]; ++i)
        std::cout << ' ' << terms[i];
    std::cout << '\n';
}

int main() {
    for (integer i = 1; i <= 10; ++i)
        classify_aliquot_sequence(i);
    for (integer i : {11, 12, 28, 496, 220, 1184, 12496, 1264460, 790, 909, 562,
                      1064, 1488})
        classify_aliquot_sequence(i);
    classify_aliquot_sequence(15355717786080);
    classify_aliquot_sequence(153557177860800);
    return 0;
}