Submission #847197

#	Time	Username	Problem	Language	Result	Execution time	Memory
847197		vjudge1	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	57 / 100	21 ms	14680 KiB

skyscraper

#include<bits/stdc++.h>
using namespace std;
const int N=3e4+5;
int n,m,p[N],b[N];
vector<int>vt[N];
int dp[N][104];

struct spm {
    int val,i,p;
};
bool operator > (spm x,spm y) {
    return x.val>y.val;
}
queue <spm> pq;

void dijkstra() {
    int ans = 1e9;
    memset(dp,0x3f,sizeof(dp));
    pq.push({0,b[0],0});
    dp[b[0]][0] = 0;
    while (!pq.empty()) {
        spm x=pq.front();
        int val=x.val,
            pw=x.p,
            i=x.i;
        if (i==b[1])
            ans=min(ans,val);
        pq.pop();
        if(val!=dp[i][pw])
            continue;
        if(pw==0){
            for(auto x:vt[i]){
                if(p[x]<=sqrt(n)) {
                    if (dp[i][p[x]]>val) {
                        dp[i][p[x]]=val;
                        pq.push({val,i,p[x]});
                    }
                }
                else{
                    int cnt=0;
                    for (int j=i;j<n;j+=p[x]){
                        if (dp[j][0]>val+cnt) {
                            dp[j][0]=val+cnt;
                            pq.push({val+cnt,j,0});
                        }
                        cnt++;
                    }
                    cnt=0;
                    for (int j=i;j>=0;j-=p[x]) {
                        if (dp[j][0]>val+cnt) {
                            dp[j][0]=val+cnt;
                            pq.push({val+cnt,j,0});
                        }
                    cnt++;
                    }
                }
            }
        }
        else {
            if(i+pw<n && dp[i+pw][pw]>val+1){
                dp[i+pw][pw]=val+1;
                pq.push({val+1,i+pw,pw});
            }
            if (i-pw>=0 && dp[i-pw][pw]>val+1){
                dp[i-pw][pw]=val+1;
                pq.push({val+1,i-pw,pw});
            }
            if (dp[i][0]>val){
                dp[i][0]=val;
                pq.push({val,i,0});
            }
        }
    }
    if(ans>=1e9)
        ans=-1;
    cout<<ans;
}

int main() {
   ios_base::sync_with_stdio(0);
   cin.tie(),cout.tie();
   cin>>n>>m;
   for (int i=0;i<m;++i) {
        cin>>b[i]>>p[i];
        vt[b[i]].push_back(i);
    }
   dijkstra();
}

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 14 / 14
• Subtask 4: 21 / 21
• Subtask 5: 0 / 43