View Compilation Error

0_0_38666632_31316.cpp: In function 'int main()':
0_0_38666632_31316.cpp:61:26: error: 'strlen' was not declared in this scope
   61 |         while(gets(str)&&strlen(str)){
      |                          ^~~~~~
0_0_38666632_31316.cpp:5:1: note: 'strlen' is defined in header '<cstring>'; did you forget to '#include <cstring>'?
    4 | #include <algorithm>
  +++ |+#include <cstring>
    5 | using namespace std;