Allowed memory size of 1610612736 bytes exhausted (tried to allocate 20480 bytes) in phar:///usr/bin/composer/src/Composer/DependencyResolver/RuleSetGenerator.php on line 64

PHP
;memory_limit=512M 
1. Firstly i find which php.ini is working because i was using multiple xampp,
  so using : php --ini
2. after that in that file i updated the memory_limit = -1    
Source

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