Compilare: user.cpp: In function ‘int main()’: user.cpp:12:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1; i<=n; i++) ^ user.cpp:14:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1; i<=m; i++) ^ user.cpp:16:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1; i<=m; i++) ^ user.cpp:20:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k=1; k<=m; k++) ^ user.cpp:24:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=k; i<=m; i++) ^ user.cpp:33:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=1;j<=n;j++) ^ user.cpp:9:22: warning: unused variable ‘k’ [-Wunused-variable] unsigned int n,m,k; ^