Submission #2872865

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Source Code Expand

#include <stdio.h>
long a[1000000];
long long sum[1000000];
long n;
long main(){
	scanf("%li",&n);
	sum[0]=0;
	for (long i=1;i<=n;i++){
		scanf("%li",&a[i]);
		sum[i]=a[i]+sum[i-1];
	}
	long long l=0;
	long long r=1000000000000000000;
	long long res=-1;
	while(l<=r){
		long long m=(l+r)/2;
		if (check(m)==1){res=m;r=m-1;}
		else l=m+1;
	}
	printf("%lli",res);
	return(0);
}
int check(long long x){
	int ans=0;
	for (long h=2;h<=n-2;h++){
		ans=1;
		long l=1;
		long r=h-1;
		long fh=1;
		long long l1,l2,h1,h2;
		while (l<=r){
			long m=(l+r)/2;
			if (sum[h]-2*sum[m]>=0){fh=m;l=m+1;}
			else r=m-1;
		}
		if (2*sum[fh+1]-sum[h]<-2*sum[fh]+sum[h]){
			fh++;	
			l1=sum[h]-sum[fh];
			h1=sum[fh];
		}
		else{
			h1=sum[h]-sum[fh];
			l1=sum[fh];
		}
		if (abs(-2*sum[fh]+sum[h])>x) ans=0;
		l=h+1;
		r=n-1;
		long sh=h+1;
		while (l<=r){
			long m=(l+r)/2;
			if ((sum[n]-sum[h])-2*(sum[m]-sum[h])>=0)						{sh=m;l=m+1;}
			else r=m-1;
		}
		if (-(sum[n]-sum[h])+2*(sum[sh+1]-sum[h])<(sum[n]-sum[h])-2*(sum[sh]-sum[h])){
			sh++;	
			l2=(sum[n]-sum[h])-(sum[sh]-sum[h]);
			h2=(sum[sh]-sum[h]);
		}
		else{
			h2=(sum[n]-sum[h])-(sum[sh]-sum[h]);
			l2=(sum[sh]-sum[h]);
		}
		if (abs((sum[n]-sum[h])-2*(sum[sh]-sum[h]))>x) 					ans=0;
		if (abs(h1-l2)>x|abs(h2-l1)>x|abs(h2-l2)>x|abs(h1-l1)>x) ans=0;
		if (ans==1){
			return(ans);
		}
	}
	
}

Submission Info

Compile Error

./Main.c: In function ‘main’:
./Main.c:17:7: warning: implicit declaration of function ‘check’ [-Wimplicit-function-declaration]
   if (check(m)==1){res=m;r=m-1;}
       ^
./Main.c: In function ‘check’:
./Main.c:45:7: warning: implicit declaration of function ‘abs’ [-Wimplicit-function-declaration]
   if (abs(-2*sum[fh]+sum[h])>x) ans=0;
       ^
./Main.c: In function ‘main’:
./Main.c:6:2: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%li",&n);
  ^
./Main.c:9:3: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%li",&a[i]);
   ^

Judge Result