Submission #261753

#	Time	Username	Problem	Language	Result	Execution time	Memory
261753		cheeheng	Climbers (RMI18_climbers)	C++14	5 / 100	270 ms	297304 KiB

climbers

#include <bits/stdc++.h>
using namespace std;

typedef pair<int, int> ii;

int h[5005];
int h3[5005];

int h2[25000005];

int dist[5005][5005];

int main(){
    int N;
    scanf("%d", &N);

    for(int i = 0; i < N; i ++){
        scanf("%d", &h[i]);
    }


    int P = 2;
    h3[0] = h[0];
    h3[1] = h[1];
    for(int i = 2; i < N; i ++){
        if(h3[i-2] >= h3[i-1] && h3[i-1] >= h3[i]){

        }
    }

    int M = 1;
    h2[0] = 0;
    for(int i = 0; i < N-1; i ++){
        if(h[i] < h[i+1]){
            for(int j = h[i]+1; j <= h[i+1]; j ++){
                h2[M++] = j;
            }
        }else if(h[i] > h[i+1]){
            for(int j = h[i]-1; j >= h[i+1]; j --){
                h2[M++] = j;
            }
        }
    }

    /*
    for(int i = 0; i < M; i ++){
        printf("%d ", h2[i]);
    }
    printf("\n");
    */

    for(int i = 0; i < M; i ++){
        //printf("h2[%d]=%d\n", i, h2[i]);
    }

    long long ans = 0;
    int A = 0;
    int B = M-1;
    memset(dist, -1, sizeof(dist));
    dist[A][B] = 0;
    queue<ii> q;
    q.push(ii(A, B));
    while(!q.empty()){
        int A, B;
        tie(A, B) = q.front(); q.pop();
        if(A == B){
            printf("%d\n", dist[A][B]);
            return 0;
        }
        //printf("while loop: %d %d %d\n", A, B, dist[A][B]);
        //printf("%d %d %d %d\n", h2[A+1], h2[A-1], h2[B+1], h2[B-1]);
        //if(ans > 100){break;}
        if(h2[A+1] == h2[B-1]){
            if(dist[A+1][B-1] == -1){
                dist[A+1][B-1] = dist[A][B]+1;
                q.push(ii(A+1, B-1));
            }
        }

        if(h2[A-1] == h2[B-1]){
            if(dist[A-1][B-1] == -1){
                dist[A-1][B-1] = dist[A][B]+1;
                q.push(ii(A-1, B-1));
            }
        }
        if(h2[A+1] == h2[B+1]){
            if(dist[A+1][B+1] == -1){
                dist[A+1][B+1] = dist[A][B]+1;
                q.push(ii(A+1, B+1));
            }
        }

    }

    ans = 1LL << 61;
    for(int i = 0; i < M; i ++){
        if(dist[i][i] == -1){continue;}
        ans = min(ans, (long long)dist[i][i]);
    }

    if(ans == (1LL << 61)){
        printf("NO");
        return 0;
    }

    printf("%lld\n", ans);
    return 0;
}

Compilation message (stderr)

climbers.cpp: In function 'int main()':
climbers.cpp:22:9: warning: unused variable 'P' [-Wunused-variable]
     int P = 2;
         ^
climbers.cpp:15:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &N);
     ~~~~~^~~~~~~~~~
climbers.cpp:18:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &h[i]);
         ~~~~~^~~~~~~~~~~~~

• Subtask 1: 0 / 25
• Subtask 2: 5 / 25
• Subtask 3: 0 / 50