ZOJ 10th Anniversary Contest - G

#include<string.h>

#include<stdio.h>



char s1[200000],s2[200000],s3[200000],s4[200000];

long long a[200000],p[200000],q[200000],num[200000],v[200000];



int main()

{

    int t,n,m,i,j,k;

    scanf("%d",&t);

    while (t-->0)

    {

          scanf(" %s",s1);

          scanf(" %s",s2);

          n=strlen(s1);

          m=strlen(s2);

          long long ans=0;

          for (i=0; i<n; i++) {num[i]=0; a[i]=0; p[i]=0; q[i]=0;}

          p[0]=-1;

          s4[0]=s2[m-1];

          for (i=1; i<m; i++)

          {

              p[i]=-1;

              int k=p[i-1];

              while ((k>-1)&&(s2[k+1]!=s2[i])) k=p[k];

              if (k>-1) p[i]=k+1;

              if ((k==-1)&&(s2[0]==s2[i])) p[i]=0;

              s4[i]=s2[m-i-1];

         }

         int mark=-1;

         for (i=0; i<n; i++)

         {

             while (mark!=-1)

             {

                   if (s1[i]==s2[mark+1]) break;

                   mark=p[mark];      

             }

             if (mark!=-1) {mark++; num[mark]++;}

             else if (s1[i]==s2[0]) {mark=0; num[mark]++;}

             a[i]=mark;

             s3[i]=s1[n-i-1];

             if (mark==m-1) mark=p[mark];

         }

         q[0]=-1;

         for (i=1; i<m; i++)

          {

              q[i]=-1;

              int k=q[i-1];

              while ((k>-1)&&(s4[k+1]!=s4[i])) k=q[k];

              if ((k==-1)&&(s4[i]==s4[0])) q[i]=0;

              if (k>-1) q[i]=k+1;

         }         

         mark=-1;

         for (i=m-1; i>=0; i--)

             if (p[i]!=-1) num[p[i]]+=num[i];

         for (i=0; i<m; i++) 

         {

             v[i]=num[m-i-2];    

             if (q[i]!=-1) v[i]+=v[q[i]];

         }

         for (i=0; i<n; i++)

         {

             while (mark!=-1)

             {

                   if (s3[i]==s4[mark+1]) break;

                   mark=q[mark];      

             }

             if (mark!=-1) mark++;

             else if (s3[i]==s4[0]) mark=0;

             ans+=v[mark];

             if (mark==m-1) mark=q[mark];

         }                

         printf("%lld\n",ans);

          

    }    

    return 0;

}