#include<stdio.h>
#include<algorithm>
#include<vector>
#include<queue>
using namespace std;
const int MAX_N = 30000, RTN = 200;
int n, m, dist[MAX_N], s, e;
bool ck[MAX_N][RTN], fvis[MAX_N];
struct st{
int b, p, w;
st(int _b, int _p, int _w)
:b(_b), p(_p), w(_w){}
};
vector<int> adj[MAX_N];
queue<st> q;
int main(){
scanf("%d %d", &n, &m);
for (int i = 0; i < m; i++){
int a, b;
scanf("%d %d", &a, &b);
adj[a].push_back(b);
if (i == 0) s = a;
if (i == 1) e = a;
}
dist[e] = -1;
q.push(st(s, 0, 0));
while (!q.empty()){
st h = q.front();
q.pop();
if (h.b < 0 || h.b >= n) continue;
if (abs(h.p) < RTN){
if (ck[h.b][abs(h.p)]) continue;
ck[h.b][abs(h.p)] = true;
}
if (!fvis[h.b]){
fvis[h.b] = true;
dist[h.b] = h.w;
for (auto t : adj[h.b]){
q.push(st(h.b + t, t, h.w + 1));
q.push(st(h.b - t, -t, h.w + 1));
}
}
q.push(st(h.b + h.p, h.p, h.w + 1));
}
printf("%d", dist[e]);
return 0;
}
Compilation message
skyscraper.cpp: In function ‘int main()’:
skyscraper.cpp:38:9: warning: ‘auto’ changes meaning in C++11; please remove it [-Wc++0x-compat]
for (auto t : adj[h.b]){
^
skyscraper.cpp:38:14: error: ‘t’ does not name a type
for (auto t : adj[h.b]){
^
skyscraper.cpp:42:3: error: expected ‘;’ before ‘}’ token
}
^
skyscraper.cpp:42:3: error: expected primary-expression before ‘}’ token
skyscraper.cpp:42:3: error: expected ‘;’ before ‘}’ token
skyscraper.cpp:42:3: error: expected primary-expression before ‘}’ token
skyscraper.cpp:42:3: error: expected ‘)’ before ‘}’ token
skyscraper.cpp:42:3: error: expected primary-expression before ‘}’ token
skyscraper.cpp:17:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &n, &m);
^
skyscraper.cpp:20:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &a, &b);
^
