Compilare: main.cpp: In function 'int main()': main.cpp:42:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < pos[val].size(); i ++) ~~^~~~~~~~~~~~~~~~~ main.cpp:43:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = i; j < pos[val].size(); j ++) { ~~^~~~~~~~~~~~~~~~~ main.cpp:47:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j + 1 < pos[val].size()) ~~~~~~^~~~~~~~~~~~~~~~~