#include<stdio.h>
#define N 100002
#define M 1000000007ll
int n,h[N],w[N],p[N],l[N],r[N];
long long pw[N];
long long z;
long long c(long long ww,long long hh)
{
ww%=M;
hh%=M;
return (((ww+1ll)*ww/2)%M*((hh+1ll)*hh/2)%M)%M;
}
void dfs(int u,int ll,int rr,int y,int yy)
{
if(!u||ll>rr)return;
long long ww=(pw[rr]-pw[ll-1]);
z = (z + (c(ww,y) + M - c(ww,yy)) % M) % M;
//printf(" AT %d : [%lld %lld], %d %lld\n",u,pw[ll-1]+1,pw[rr],y,z);
dfs(l[u],ll,u-1,h[l[u]],y);
dfs(r[u],u+1,rr,h[r[u]],y);
}
int main()
{
scanf("%d",&n);
for(int i=1;i<=n;++i)scanf("%d",h+i);
for(int i=1;i<=n;++i)scanf("%d",w+i),pw[i]=pw[i-1]+w[i];
for(int i=1;i<=n;++i)
{
p[i]=i-1;
while(h[p[i]]>h[i])p[i]=p[p[i]];
l[i]=r[p[i]];
r[p[i]]=i;
p[l[i]]=i;
}
for(int i=1;i<=n;++i)if(!p[i])dfs(i,1,n,h[i],0);
printf("%lld",z);
}
Compilation message
fancyfence.c: In function 'main':
fancyfence.c:28:5: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
28 | scanf("%d",&n);
| ^~~~~~~~~~~~~~
fancyfence.c:29:26: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
29 | for(int i=1;i<=n;++i)scanf("%d",h+i);
| ^~~~~~~~~~~~~~~
fancyfence.c:30:26: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
30 | for(int i=1;i<=n;++i)scanf("%d",w+i),pw[i]=pw[i-1]+w[i];
| ^~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
344 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
1 ms |
348 KB |
Output is correct |
3 |
Correct |
9 ms |
1628 KB |
Output is correct |
4 |
Correct |
19 ms |
2908 KB |
Output is correct |
5 |
Correct |
21 ms |
2904 KB |
Output is correct |
6 |
Correct |
17 ms |
3164 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
348 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Incorrect |
1 ms |
344 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |