/in/lab5.c: In function 'remove_spaces':
/in/lab5.c:20:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i=0;i<=strlen(str);i++)
                   ^~
/in/lab5.c: In function 'find_left_variable':
/in/lab5.c:41:9: warning: unused variable 'variable_len' [-Wunused-variable]
     int variable_len=pch-formerstr;
         ^~~~~~~~~~~~
/in/lab5.c: In function 'main':
/in/lab5.c:110:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 for (int i = 0; i < strlen(infix); i++) {
                   ^
/in/lab5.c:292:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 for (int i = 0; i < strlen(infix); i++) {
                   ^
/in/lab5.c: In function 'compare':
/in/lab5.c:14:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^