Submission #1569348

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Source Code Expand

#include <functional>
#include <algorithm>
#include <iostream>
#include <memory.h>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <assert.h>
#include <bitset>
#include <string>
#include <cstdio>
#include <math.h>
#include <complex>
#include <vector>
#include <queue>
#include <stack>
#include <cmath>
#include <ctime>
#include <set>
#include <bitset>
#include <map>
using namespace std;

#define int64 long long
#define mp make_pair
#define ull unsigned long long


#ifdef _DEBUG
	const int N = 101;
#else
	const int N = 500000;
#endif
const int M = 70; 

const int MOD = 1e9+7;

int n, a[N], b[N];
pair <int, int> p[N];
map <int, vector<int> >	q;

int main()
{
#ifdef _DEBUG
	freopen("input.txt", "r", stdin);
	freopen("output.txt", "w", stdout);
#endif
	scanf("%d", &n);
	for (int i = 1; i <= n; i++) scanf("%d", &a[i]);
	for (int i = 1; i <= n; i++) scanf("%d", &b[i]);
	for (int i = 1; i <= n; i++)
		if (a[i] != b[i])
		{
			q[b[i]].push_back(i);
		}
	int x = 0;
	for (int i = 1; i <= n; i++) x ^= a[i];
	int need = 0;
	for (int i = 1; i <= n; i++)
		if (a[i] != b[i])
		{
			need++;
		}
	int ans = 0;
	int p = 0;
	int it = 3 * n;
	while (it-- && need)
	{
		if (q.find(x) != q.end())
		{
			ans++;
			int j = q[x].back();
			q[x].pop_back();
			if (q[x].empty()) q.erase(x);
			x = a[j];
			a[j] = b[j];
			need--;
		}
		else
		{
			ans++;
			if (q.empty()) break;
			int s = (*q.begin()).first;
			int j = q[s].back();
			int tmp = a[j];
			a[j] = x;
			x = tmp;
		}
	}
	for (int i = 1; i <= n; i++)
		if (a[i] != b[i]) ans = -1;
	cout << ans;
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:48:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
                 ^
./Main.cpp:49:49: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  for (int i = 1; i <= n; i++) scanf("%d", &a[i]);
                                                 ^
./Main.cpp:50:49: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  for (int i = 1; i <= n; i++) scanf("%d", &b[i]);
                                                 ^

Judge Result