Hey beautiful people out there,\nI\'ve been practicising dp these days, and i use memoization to solve problems. Many a times i\'ve seen that whenever i pass a vector or string as an argument to a function without an amersand (&) i get a TLE or MLE, while adding an ampersand immediately removes it. \neg -\n\n\t\tint calc(vector<int> a)\n\t\t{\n\t\t............. (funciton definition)\n\t\t}\n// TLE/MLE, WHILE \n```\nint calc(vector<int> &a)\n\t{\n\t\t..........\n\t}\n```\nThis works perfectly fine. Why is it so? What difference does this ampersand makes?

Hey beautiful people out there,\nI\'ve been practicising dp these days, and i use memoization to solve problems. Many a times i\'ve seen that whenever i pass a 