Submission #845972

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Source Code Expand

#include<iostream>
#include<algorithm>

using namespace std;

int const N = 1e5 + 41;

int n, a[N], ans, b[N];

int getPos(int v){
	int l = -1;
	int r = n;
	while(r-l>1){
		int m = (l+r);
		if(b[m] <= v){
			l = m;
		}else{
			r = m;
		}
	}
	return l;
}

int main(){
	scanf("%d",&n);
	for(int i=0;i<n;++i){
		scanf("%d",&a[i]);
		b[i] = a[i];
	}
	if(n == 1){
		printf("%d\n", ans);
		return 0;
	}
	if(n == 2){
		if(a[0] > a[1]){
			++ans;
		}
		printf("%d\n",ans);
		return 0;
	}

	sort(b, b+n);
	for(int i=0;i<n;++i){
		if((i % 2) != getPos(a[i]) % 2){
			++ans;
		} 
	}
	ans /= 2;
	printf("%d\n",ans);




	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:25:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
                ^
./Main.cpp:27:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&a[i]);
                    ^

Judge Result