Compilare: user.cpp: In function ‘bool ok(int)’: user.cpp:21:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( int i = 0; i < A[x].size(); i++ ) { ^ user.cpp: In function ‘int main()’: user.cpp:61:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( int i = 0; i < A[x].size(); i++ ) { ^ user.cpp:65:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (Uz[y] <= A[y].size() - 1) { ^ user.cpp:69:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (Uz[y] == A[y].size() - 1) { ^ user.cpp:73:48: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( int j = 0; j < A[y].size(); j++ ) { ^ user.cpp:74:56: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (Uz[A[y][j]] == A[A[y][j]].size()) ^ user.cpp:78:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] else if (Uz[y] == A[y].size()) { ^