Update solution

problems/88/main.cpp

 #include <algorithm>
 
 void merge(std::vector<int>& nums1, int m, std::vector<int>& nums2, int n) {
-    int total = m + n;
     while (n > 0) {
         nums1[m++] = nums2[--n];
     }
     }
     std::cout << " ]" << std::endl;
     return 0;
-}
+}