Submission #158881

#TimeUsernameProblemLanguageResultExecution timeMemory
158881Ruxandra985캥거루 (CEOI16_kangaroo)C++14
51 / 100
118 ms76564 KiB
#include <cstdio>
#include <iostream>
#define MOD 1000000007
using namespace std;
int c[210][210][210] , d[210][210][210];
int main()
{
    FILE *fin = stdin;
    FILE *fout = stdout;
    int n , cs , cf , len , bgn , ed;
    fscanf (fin,"%d%d%d",&n,&cs,&cf);

    if (cs > cf)
        swap(cs , cf);

    c[2][1][2] = d[2][2][1] = 1;

    for (len = 3 ; len <= n ; len++){
        for (bgn = 1 ; bgn <= len ; bgn++){
            for (ed = bgn + 1 ; ed <= len ; ed ++){
                if (bgn!=1)
                    c[len][bgn][ed] = ((c[len][bgn-1][ed] - d[len-1][bgn-1][ed-1])%MOD + MOD )%MOD;
                else {
                    for (int bgn2 = bgn+1 ; bgn2 <= len ; bgn2++)
                        c[len][bgn][ed] = (c[len][bgn][ed] + d[len-1][bgn2][ed-1])%MOD;
                }
                d[len][bgn][ed] = (d[len][bgn-1][ed] + c[len-1][bgn-1][ed-1])%MOD;

                if (len%2 == 1){
                    d[len][ed][bgn] = d[len][bgn][ed];
                    c[len][ed][bgn] = c[len][bgn][ed];
                }
                else {
                    d[len][ed][bgn] = c[len][bgn][ed];
                    c[len][ed][bgn] = d[len][bgn][ed];
                }

            }
        }
    }



    fprintf (fout,"%d",(c[n][cs][cf] + d[n][cs][cf])%MOD);
    return 0;
}

Compilation message (stderr)

kangaroo.cpp: In function 'int main()':
kangaroo.cpp:11:12: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     fscanf (fin,"%d%d%d",&n,&cs,&cf);
     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...