C++经典算法题-完美数

#include <stdio.h> 
#include <stdlib.h>
#define N 1000
#define P 10000

    int prime(int*);	// 求质数表
    int factor(int*, int, int*);	// 求factor
    int fsum(int*, int);	// sum ot proper factor


    int main(void) {
        int ptable[N+1] = {0}; // 储存质数表
        int fact[N+1] = {0};	// 储存因式分解结果
        int count1, count2, i; count1 = prime(ptable);
        for(i = 0; i <= P; i++) {
            count2 = factor(ptable, i, fact); if(i == fsum(fact, count2))
                printf("Perfect Number: %d\n", i);
        }

        printf("\n");

        return 0;
    }

    int prime(int* pNum) { int i, j;
        int prime[N+1];

        for(i = 2; i <= N; i++) prime[i] = 1;

        for(i = 2; i*i <= N; i++) { if(prime[i] == 1) {
            for(j = 2*i; j <= N; j++) { if(j % i == 0)
                prime[j] = 0;
            }
        }
        }

        for(i = 2, j = 0; i < N; i++) { if(prime[i] == 1)
            pNum[j++] = i;
        }

        return j;

    }

    int factor(int* table, int num, int* frecord) { int i, k;

        for(i = 0, k = 0; table[i] * table[i] <= num;) { if(num % table[i] == 0) {
            frecord[k] = table[i]; k++;
            num /= table[i];

        }
        else

        }



        i++;


        frecord[k] = num;

        return k+1;
    }

    int fsum(int* farr, int c) { int i, r, s, q;

        i = 0;
        r = 1;
        s = 1;
        q = 1;

        while(i < c) { do {
            r *= farr[i]; q += r; i++;
        } while(i < c-1 && farr[i-1] == farr[i]); s *= q;
            r = 1;
            q = 1;
        }

        return s / 2;
    }