#include<iostream>

 #include<cstdio>

 #include<cstring>

 using namespace std;

 typedef char* String;

 int len1,len2;

 char S[];

 char T[];

 void get_next(String T,int *next){

     int j = ;

     int i = ;

     next[] = ;

     while( i<len2 ){

         if(==j || T[i]==T[j])

         {

             i++;

             j++;

             next[i] = j;

         }

         else{

             j = next[j];

         }

     }

 }

 int Index_KMP(String S,String T,int pos){

     int i=pos;

     int j=;

     int next[];

     get_next(T,next);

     while(i<=len1&&j<=len2){

         if(j==||S[i]==T[j]){

             i++;

             j++;

         }

         else{

             j=next[j];

         }

     }

     if(j>len2){

         return i-len2;

     }

     else

         return -;

 }

 int main(){

     int n;

     cin>>n;

     while(n--){

         scanf("%s%s",S+,T+);

         len1 = strlen(S+);

         len2 = strlen(T+);

         printf("%d\n",Index_KMP(S,T,));

     }

     return ;

 }

 //BF算法

 #include<iostream>

 #include<cstdio>

 #include<cstring>

 using namespace std;

 char s[],t[];

 int len1,len2;

 int main(){

     int n;

     cin>>n;

     while(n--){

         scanf("%s%s",s,t);

         len1 = strlen(s);

         len2 = strlen(t);

         int i = ,j = ;

         while( i < len1 && j < len2 ){

             if( s[i] == t[j] ){

                 i++;

                 j++;

             }

             else{

                 i = i-j+;

                 j = ;

             }

         }

         if( j == len2 )

             cout<<i-j+<<endl;

         else

             cout<<"-1"<<endl;

     }

     return ;

 }