題目連結

#include<cstdio>
#include<algorithm>
using namespace std;
typedef long long ll;
const int MAXN=1e7+10;
ll a[MAXN];
int r[MAXN],N,ans=1;
#define RG register
#define getc() (S == T && (T = (S = B) + fread(B, 1, 1 << 15, stdin), S == T) ? EOF : *S++)
char B[1 << 15], *S = B, *T = B;
inline long long F() {
	RG char ch; RG long long x = 0; RG bool m = 0;
	while (ch = getc(), (ch < '0' || ch > '9') && ch != '-') ;
	ch == '-' ? m = 1 : x = ch - '0';
	while (ch = getc(), ch >= '0' && ch <= '9') x = x * 10 + ch - '0';
	return m ? -x : x;
}
int main()
{
	//freopen("in.txt","r",stdin);
	N=F();ll v;
	for(int i = 1; i <= N; ++i) a[i] = F();
    for(int i = 1, j = 1; i <= N; ++i) {v = a[i]; while(j <= N && a[j] % v == 0) ++j; r[i] = j;}
	for(int i = N, j = N; i >= 1; --i) {v = a[i]; while(j >= 1 && a[j] % v == 0) --j; if(r[i] - j - 1 > ans) ans = r[i] - j - 1;}
	printf("%d\n",ans);
	return 0;
}
 

總結

無