Compilare: user.cpp: In function ‘std::vector<int> add(std::vector<int>, std::vector<int>)’: user.cpp:10:51: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < std::max(a.size(), b.size()) || t > 0; i++) { ^ user.cpp:11:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i < a.size()) ^ user.cpp:13:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i < b.size()) ^ user.cpp: In function ‘std::vector<int> product(std::vector<int>, int)’: user.cpp:27:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < a.size() || t > 0; i++) { ^ user.cpp:28:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i < a.size()) ^ user.cpp: In function ‘int main()’: user.cpp:49:45: warning: suggest parentheses around ‘-’ in operand of ‘&’ [-Wparentheses] dp[i & 1][j] = add(product(dp[1 - i & 1][j], i - 1), dp[1 - i & 1][j - 1]); ^ user.cpp:49:71: warning: suggest parentheses around ‘-’ in operand of ‘&’ [-Wparentheses] dp[i & 1][j] = add(product(dp[1 - i & 1][j], i - 1), dp[1 - i & 1][j - 1]); ^ user.cpp:44:31: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d %d " ,&n,&k); ^