Submission #1547928

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Source Code Expand

#include <stdio.h>
#include <stdlib.h>

#define MAX_N 100000
#define MAX_A 1000000000

long long int valid_num = 0;
long long int valid[MAX_N];

long long int hash[MAX_N*10];

long long int rehash_f(long long int num, int plus_num){
	return (num + plus_num + rand()) % (MAX_N*10);
}

long long int hash_f(long long int num)
{
	srand(10);
	int b = (num + rand()) % (MAX_N*10);
	if(hash[b] == num){
		hash[b] = 0;
		valid[valid_num] = num;
		valid_num++;
	}
	else if(hash[b] != 0){
		for(int i = 1; hash[b] != 0; i++){
			b = rehash_f(num, i);
			if(hash[b] == num){
				hash[b] = 0;
				valid[valid_num] = num;
				valid_num++;
			}
		}
		hash[b] = num;
	}
	else {
		hash[b] = num;
	}
}

int main()
{
	long long int a[MAX_N];
	long long int N;
	long long int s;

	for(int i = 0; i < N; i++){
		hash[i] = 0;
	}

	scanf("%lld", &N);
	for(int i = 0; i < N; i++){
		scanf("%lld", &a[i]);
		hash_f(a[i]);
	}

	if(valid_num >= 2){
		long long int tmp = valid[0];
		long long int max_i = 0;
		for(int i = 1; i < valid_num; i++){
			if(tmp < valid[i]){
				tmp = valid[i];
				max_i = i;
			}
		}
		valid[max_i] = 0;
		s = tmp;
		tmp = valid[0];
		max_i = 0;
		for(int i = 1; i < valid_num; i++){
			if(tmp < valid[i]){
				tmp = valid[i];
				max_i = i;
			}
		}
		s = s * tmp;

		printf("%lld\n", s);
	} else {
		printf("0\n");
	}
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:51:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld", &N);
                   ^
./Main.cpp:53:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lld", &a[i]);
                       ^

Judge Result