Compilare: user.cpp: In function ‘int main()’: user.cpp:22:53: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=1,k=0;j<=nr || k<v2[i-1].size();) ^ user.cpp:23:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if((k<v2[i-1].size() && j<=nr) && v[j]==v2[i-1][k]) ^ user.cpp:26:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j<=nr && (k==v2[i-1].size() || v[j]<v2[i-1][k])) ^ user.cpp:41:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0,k=0;j<v2[a].size() || k<v2[b].size();) ^ user.cpp:41:60: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0,k=0;j<v2[a].size() || k<v2[b].size();) ^ user.cpp:42:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if((j<v2[a].size() && k<v2[b].size()) && v2[a][j]==v2[b][k]) ^ user.cpp:42:52: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if((j<v2[a].size() && k<v2[b].size()) && v2[a][j]==v2[b][k]) ^ user.cpp:45:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j<v2[a].size() && (k==k<v2[b].size() || v2[a][j]<v2[b][k])) ^ user.cpp:45:59: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j<v2[a].size() && (k==k<v2[b].size() || v2[a][j]<v2[b][k])) ^ user.cpp:45:47: warning: suggest parentheses around comparison in operand of ‘==’ [-Wparentheses] if(j<v2[a].size() && (k==k<v2[b].size() || v2[a][j]<v2[b][k])) ^