Compilare: main.cpp: In function 'int main()': main.cpp:48:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < st[ind].size(); j++) { ~~^~~~~~~~~~~~~~~~ main.cpp:55:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < dr[ind].size(); j++) { ~~^~~~~~~~~~~~~~~~ main.cpp:61:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(nrst >= l) { ~~~~~^~~~ main.cpp:63:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < st[ind].size(); j++) { ~~^~~~~~~~~~~~~~~~ main.cpp:76:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(nrdr > u) { ~~~~~^~~ main.cpp:78:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < dr[ind].size(); j++) { ~~^~~~~~~~~~~~~~~~ main.cpp: In function 'char nxt()': main.cpp:21:31: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, DIM, stdin); ^ main.cpp: In function 'int main()': main.cpp:40:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.in", "r", stdin); ^ main.cpp:41:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.out", "w", stdout); ^