Compilare: main.cpp: In function 'int main()': main.cpp:40:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( k = 0; k < vec[j].size ( ); k++ ){ ~~^~~~~~~~~~~~~~~~~ main.cpp:61:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( k = 0; k < vec[i].size ( ); k++ ){ ~~^~~~~~~~~~~~~~~~~ main.cpp:66:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( k = 0; k < vec[i].size ( ); k++ ){ ~~^~~~~~~~~~~~~~~~~ main.cpp:24:38: warning: unused variable 'l' [-Wunused-variable] int mod[] = { 0, -m, 1, m, -1 }, l = 0, MAX = n * m, Height = 0; ^