Submission #154740

#	Time	Username	Problem	Language	Result	Execution time	Memory
154740		arnold518	PIN (CEOI10_pin)	C++14	0 / 100	158 ms	3064 KiB

pin

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

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 5e4;

int N, D;
int A[MAXN+10][5], T[5]={1, 40, 40*40, 40*40*40};
ll arr[5], ans[5];

int f(char x)
{
    if('0'<=x && x<='9') return x-'0';
    else return x-'a'+10;
}

void solve()
{
    int i, j, k, p, q;
    for(i=0; i<4; i++)
    {
        map<int, int> M;
        for(j=1; j<=N; j++)
        {
            ans[1]+=M[A[j][4]-A[j][i]];
            M[A[j][4]-A[j][i]]++;
        }
    }

    for(i=0; i<4; i++)
    {
        for(j=i+1; j<4; j++)
        {
            map<int, int> M;
            for(k=1; k<=N; k++)
            {
                arr[2]+=M[A[k][4]-A[k][i]-A[k][j]];
                M[A[k][4]-A[k][i]-A[k][j]]++;
            }
        }
    }

    for(i=0; i<4; i++)
    {
        map<int, int> M;
        for(j=1; j<=N; j++)
        {
            arr[3]+=M[A[j][i]];
            M[A[j][i]]++;
        }
    }

    ans[1]=arr[1];
    ans[2]=arr[2]-3*arr[1];
    ans[3]=arr[3]-2*arr[2]+3*arr[1];
    ans[4]=(ll)N*(N-1)/2-ans[1]-ans[2]-ans[3];
}

int main()
{
    int i, j;

    scanf("%d%d", &N, &D);
    for(i=1; i<=N; i++)
    {
        char s[5];
        scanf("%s", s);
        A[i][0]=f(s[0])*T[0];
        A[i][1]=f(s[1])*T[1];
        A[i][2]=f(s[2])*T[2];
        A[i][3]=f(s[3])*T[3];
        A[i][4]=A[i][0]+A[i][1]+A[i][2]+A[i][3];
    }
    solve();
    printf("%lld", ans[D]);
}

Compilation message (stderr)

pin.cpp: In function 'void solve()':
pin.cpp:22:18: warning: unused variable 'p' [-Wunused-variable]
     int i, j, k, p, q;
                  ^
pin.cpp:22:21: warning: unused variable 'q' [-Wunused-variable]
     int i, j, k, p, q;
                     ^
pin.cpp: In function 'int main()':
pin.cpp:64:12: warning: unused variable 'j' [-Wunused-variable]
     int i, j;
            ^
pin.cpp:66:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d", &N, &D);
     ~~~~~^~~~~~~~~~~~~~~~
pin.cpp:70:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%s", s);
         ~~~~~^~~~~~~~~

• Subtask 1: 0 / 100