#include<string.h>
#include<stdio.h>
#include<utility>
#include<queue>
#define N 30000
#define S 170
#define N1 2*(S*N+N+N)
int lo(int a,int b){return a<b?a:b;}
int z=1e9,n,m,b[N],p[N],e[N1][3],ne,h[N1],d[N1];
void link(int u,int v,int w) {e[++ne][0]=v,e[ne][1]=w,e[ne][2]=h[u],h[u]=ne;}
int bp(int bb,int pp){return bb+30000*pp+30000;}
int main()
{
scanf("%d%d",&n,&m);
for(int i=0;i<m;++i){
scanf("%d%d",b+i,p+i);
if(p[i]<S){
link(b[i],bp(b[i],p[i]),0);
}else{
for(int dd=1,j=b[i]-p[i];j>=0;j-=p[i],++dd)link(b[i],b[j],dd);
for(int dd=1,j=b[i]+p[i];j<N;j+=p[i],++dd)link(b[i],b[j],dd);
}
}
memset(d,63,sizeof d);
std::priority_queue<std::pair<int,int>>pq;
pq.emplace(-(d[b[0]]=0),b[0]);
while(pq.size())
{
auto[c,u]=pq.top();c=-c;pq.pop();
if(d[u]-c)continue;
for(int j=h[u];j;j=e[j][2])if(d[e[j][0]]>c+e[j][1])
pq.emplace(-(d[e[j][0]]=c+e[j][1]),e[j][0]);
if(u>=30000){
int bb,pp;
bb=(u-30000)%30000;
pp=(u-30000)/30000;
if(bb==b[1])z=lo(z,c);
//printf("AT %d %d\n",bb,pp);
if(d[bb]>c)pq.emplace(-(d[bb]=c),bb);
if(bb>=pp&&d[bp(bb-pp,pp)]>c+1)pq.emplace(-(d[bp(bb-pp,pp)]=c+1),bp(bb-pp,pp));
if(bb+pp<n&&d[bp(bb+pp,pp)]>c+1)pq.emplace(-(d[bp(bb+pp,pp)]=c+1),bp(bb+pp,pp));
} else
{
//printf("AT %d\n",u);
if(u==b[1])z=lo(z,c);
}
}
if(z<1e9)printf("%d",z);else puts("-1");
}
Compilation message
skyscraper.cpp: In function 'int main()':
skyscraper.cpp:16:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
16 | scanf("%d%d",&n,&m);
| ~~~~~^~~~~~~~~~~~~~
skyscraper.cpp:18:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
18 | scanf("%d%d",b+i,p+i);
| ~~~~~^~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
42844 KB |
Output is correct |
2 |
Correct |
6 ms |
42844 KB |
Output is correct |
3 |
Correct |
7 ms |
42844 KB |
Output is correct |
4 |
Correct |
6 ms |
42844 KB |
Output is correct |
5 |
Correct |
6 ms |
42844 KB |
Output is correct |
6 |
Correct |
6 ms |
42840 KB |
Output is correct |
7 |
Correct |
6 ms |
42844 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
42844 KB |
Output is correct |
2 |
Correct |
6 ms |
42844 KB |
Output is correct |
3 |
Correct |
6 ms |
42840 KB |
Output is correct |
4 |
Correct |
6 ms |
42744 KB |
Output is correct |
5 |
Correct |
6 ms |
42844 KB |
Output is correct |
6 |
Correct |
6 ms |
42844 KB |
Output is correct |
7 |
Correct |
6 ms |
42844 KB |
Output is correct |
8 |
Correct |
6 ms |
42844 KB |
Output is correct |
9 |
Correct |
6 ms |
42844 KB |
Output is correct |
10 |
Correct |
6 ms |
42844 KB |
Output is correct |
11 |
Correct |
7 ms |
42844 KB |
Output is correct |
12 |
Correct |
6 ms |
42844 KB |
Output is correct |
13 |
Correct |
7 ms |
42844 KB |
Output is correct |
14 |
Correct |
7 ms |
42844 KB |
Output is correct |
15 |
Correct |
7 ms |
42844 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
42844 KB |
Output is correct |
2 |
Correct |
6 ms |
42844 KB |
Output is correct |
3 |
Correct |
6 ms |
42844 KB |
Output is correct |
4 |
Correct |
7 ms |
42756 KB |
Output is correct |
5 |
Correct |
6 ms |
42840 KB |
Output is correct |
6 |
Correct |
6 ms |
42684 KB |
Output is correct |
7 |
Correct |
6 ms |
42840 KB |
Output is correct |
8 |
Correct |
6 ms |
42844 KB |
Output is correct |
9 |
Correct |
6 ms |
42708 KB |
Output is correct |
10 |
Correct |
6 ms |
42840 KB |
Output is correct |
11 |
Correct |
6 ms |
42844 KB |
Output is correct |
12 |
Correct |
6 ms |
42732 KB |
Output is correct |
13 |
Correct |
6 ms |
42844 KB |
Output is correct |
14 |
Correct |
7 ms |
42952 KB |
Output is correct |
15 |
Correct |
8 ms |
42748 KB |
Output is correct |
16 |
Incorrect |
7 ms |
43096 KB |
Output isn't correct |
17 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
42840 KB |
Output is correct |
2 |
Correct |
6 ms |
42840 KB |
Output is correct |
3 |
Correct |
7 ms |
42844 KB |
Output is correct |
4 |
Correct |
6 ms |
42840 KB |
Output is correct |
5 |
Correct |
7 ms |
42844 KB |
Output is correct |
6 |
Correct |
6 ms |
42844 KB |
Output is correct |
7 |
Correct |
6 ms |
42844 KB |
Output is correct |
8 |
Correct |
6 ms |
42844 KB |
Output is correct |
9 |
Correct |
7 ms |
42844 KB |
Output is correct |
10 |
Correct |
6 ms |
42844 KB |
Output is correct |
11 |
Correct |
6 ms |
42844 KB |
Output is correct |
12 |
Correct |
6 ms |
42840 KB |
Output is correct |
13 |
Correct |
6 ms |
42844 KB |
Output is correct |
14 |
Correct |
7 ms |
42708 KB |
Output is correct |
15 |
Correct |
6 ms |
42844 KB |
Output is correct |
16 |
Incorrect |
7 ms |
43100 KB |
Output isn't correct |
17 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
42844 KB |
Output is correct |
2 |
Correct |
7 ms |
42844 KB |
Output is correct |
3 |
Correct |
5 ms |
42844 KB |
Output is correct |
4 |
Correct |
6 ms |
42840 KB |
Output is correct |
5 |
Correct |
6 ms |
42844 KB |
Output is correct |
6 |
Correct |
6 ms |
42844 KB |
Output is correct |
7 |
Correct |
6 ms |
42844 KB |
Output is correct |
8 |
Correct |
6 ms |
42796 KB |
Output is correct |
9 |
Correct |
6 ms |
42844 KB |
Output is correct |
10 |
Correct |
6 ms |
42840 KB |
Output is correct |
11 |
Correct |
7 ms |
42844 KB |
Output is correct |
12 |
Correct |
6 ms |
42844 KB |
Output is correct |
13 |
Correct |
7 ms |
42844 KB |
Output is correct |
14 |
Correct |
7 ms |
42844 KB |
Output is correct |
15 |
Correct |
6 ms |
42844 KB |
Output is correct |
16 |
Incorrect |
7 ms |
43100 KB |
Output isn't correct |
17 |
Halted |
0 ms |
0 KB |
- |