Compilare: main.cpp: In function 'void write()': main.cpp:157:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < output.size(); i++) { ~~^~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:186:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j + add < g[i].size(); j++) { ~~~~~~~~^~~~~~~~~~~~~