Compilare: main.cpp: In function 'int main()': main.cpp:19:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<m; ++i){ ~^~ main.cpp:26:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<n; ++i){ ~^~ main.cpp:30:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=i+1, k=0; j<n; ++j){ ~^~ main.cpp:38:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<n; ++i) ~^~