Submission #1779645

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Source Code Expand

#include<cstdio>
#include<iostream>
#include<vector>
#include<queue>
#include<bitset>
#include<string>
#include<stack>
#include<set>
#include<map>
#include<cstring>
#include<complex>
#include<cmath>
#include<algorithm>
#include<list>
#include<functional>
#define _USE_MATH_DEFINES
#define X first
#define Y second
#define INF 1987654321
#define PI 3.14159265358979323846264
#define MOD 1000000007
#define fup(i,a,b,c) for(int (i)=(a);(i)<=(b);(i)+=(c))
#define fdn(i,a,b,c) for(int (i)=(a);(i)>=(b);(i)-=(c))
#define MEM0(a) memset(a,0,sizeof(a));
#define MEM_1(a) memset(a,-1,sizeof(a));
using namespace std;
typedef long long ll;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int, int> Pi;
typedef pair<ll, ll> Pll;
typedef pair<double, double> Pd;
typedef vector<int> Vi;
typedef vector<ll> Vll;
typedef vector<double> Vd;
typedef vector<Pi> VPi;
typedef vector<Pll> VPll;
typedef vector<Pd> VPd;
typedef complex<double> base;
ll POW(ll a, ll b) { if (b == 0)return 1; if (b == 1)return a; if (b & 1)return (a*POW(a, b - 1)) % MOD; ll t = POW(a, b / 2); return (t*t) % MOD; }
struct num {
	int x, i;
	bool operator <(const num& a)
	{
		return x < a.x;
	}
}a[100000];
int main() {
	int n;
	scanf("%d", &n);
	fup(i, 0, n - 1, 1)
	{
		scanf("%d", &a[i].x);
		a[i].i = i;
	}
	sort(a, a + n);
	int ans = 0;
	fup(i, 0, n - 1, 1) if ((i^a[i].i) & 1)ans++;
	printf("%d", ans / 2);
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:50:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
                 ^
./Main.cpp:53:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &a[i].x);
                       ^

Judge Result