Compilare: user.cpp: In function ‘void calc()’: user.cpp:103:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 1 ; j < g[i].size(); ++j) ~~^~~~~~~~~~~~~ user.cpp:105:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0 ; j < g[i].size(); ++j) { ~~^~~~~~~~~~~~~ user.cpp:100:13: warning: unused variable ‘lenn’ [-Wunused-variable] int lenn = g[i].size(); ^~~~ user.cpp:124:17: warning: unused variable ‘ll’ [-Wunused-variable] int ll = sum[j].size() - 1; ^~ user.cpp: In function ‘int main()’: user.cpp:140:18: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses] cin >> s + 1; ~~^~~ user.cpp:136:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("brackets2.in", "r", stdin); ^