answer.code: In function ‘int main()’:
answer.code:166:9: error: ‘memset’ was not declared in this scope
  166 |         memset( fir , -1 , sizeof(fir) ) ;
      |         ^~~~~~
answer.code:3:1: note: ‘memset’ is defined in header ‘<cstring>’; did you forget to ‘#include <cstring>’?
    2 | #include <iostream>
  +++ |+#include <cstring>
    3 | using namespace std ;
answer.code:169:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  169 |         scanf( "%d%d" , &n , &m ) ;
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~
answer.code:172:22: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  172 |                 scanf( "%d%d" , &t1 , &t2 ) ;
      |                 ~~~~~^~~~~~~~~~~~~~~~~~~~~~
answer.code:223:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  223 |         scanf( "%d" , &l ) ;
      |         ~~~~~^~~~~~~~~~~~~
answer.code:226:22: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  226 |                 scanf( "%d%d" , &t1 , &t2 ) ;
      |                 ~~~~~^~~~~~~~~~~~~~~~~~~~~~