Submission #27771

#	Time	Username	Problem	Language	Result	Execution time	Memory
27771		TAMREF	Palembang Bridges (APIO15_bridge)	C++11	22 / 100	86 ms	2800 KiB

bridge

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int Q[100005], R[100005], K, N;
ll ans, ans2;
inline ll pro(int x){
    ll u=0;
    for(int i=0;i<N;i++){
        u+=abs((ll)x-Q[i])+abs((ll)x-R[i]);
    }
    return u;
}
void solve1(){
    int p=0,q,r,s=1e9;
    while(p<s){
        q=p+(s-p)/3;
        r=s-(s-p)/3;
        if(pro(q)<=pro(r)) s=r-1;
        else p=q+1;
    }
    ans+=pro(p);
}
void solve2(){
    ll C[205];
    for(int i=0;i<N;i++) C[i<<1]=Q[i],C[i<<1|1]=R[i];
    sort(C,C+2*N);
    int x=unique(C,C+2*N)-C;
    ll add=1e18,tmp;
    for(int i=0;i<x;i++){
        for(int j=i;j<x;j++){
            tmp=0;
            for(int k=0;k<N;k++){
                tmp+=min(llabs((ll)Q[k]-C[i])+llabs((ll)R[k]-C[i]),
                         llabs((ll)Q[k]-C[j])+llabs((ll)R[k]-C[j]));
            }
            add=min(add,tmp);
        }
    }
    ans+=add;
}
int main(){
    scanf("%d %d",&K,&N);
    char u,v;
    for(int i=0;i<N;i++){
        getchar();
        u=getchar();
        scanf(" %d ",&Q[i]);
        v=getchar();
        scanf(" %d",&R[i]);
        if(u==v){
            ans+=abs(Q[i]-R[i]);
            --i;--N;
        }else{
            ++ans;
            if(u=='B') swap(Q[i],R[i]);
        }
    } ans2=ans;
    if(K==1) solve1();
    else solve2();
    printf("%lld\n",ans);
}

Compilation message (stderr)

bridge.cpp: In function 'int main()':
bridge.cpp:42:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d",&K,&N);
                         ^
bridge.cpp:47:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf(" %d ",&Q[i]);
                            ^
bridge.cpp:49:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf(" %d",&R[i]);
                           ^

• Subtask 1: 8 / 8
• Subtask 2: 14 / 14
• Subtask 3: 0 / 9
• Subtask 4: 0 / 32
• Subtask 5: 0 / 37