Compilare: main.cpp: In function 'int main()': main.cpp:99:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<strlen(s); i++) ~^~~~~~~~~~ main.cpp:125:13: warning: unused variable 'nr' [-Wunused-variable] int nr=0; ^~ main.cpp:98:9: warning: unused variable 'n' [-Wunused-variable] int n=0; ^ main.cpp:95:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("exp.in", "r", stdin); ^ main.cpp:96:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("exp.out", "w", stdout); ^ main.cpp:97:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%s", s); ^