Compilare: user.cpp: In function ‘int main()’: user.cpp:38:54: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=1;i<=50;i++) if (i*(i+1)*(2*i+1)/6 == n) { ^ user.cpp:42:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int l=1;l<=m;l++) { ^ user.cpp:48:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int l=1;l<m;l++) { ^ user.cpp:56:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=1;i<=m;i++) for (int j=1;j<=m;j++) if (b[m][i][j] < mx) { ^ user.cpp:56:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=1;i<=m;i++) for (int j=1;j<=m;j++) if (b[m][i][j] < mx) { ^ user.cpp:67:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (b[l-1][i-1][j-1] <= mx && i >= 2 && j >= 2) i=in-1,j=jn-1,mx = b[l-1][i-1][j-1]; ^ user.cpp:68:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (b[l-1][i-1][j] < mx && i >= 2) i=in-1,mx = b[l-1][i-1][j]; ^ user.cpp:69:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (b[l-1][i][j-1] < mx && j >= 2) j=jn-1; ^ user.cpp:70:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (b[l-1][i][j] < mx && b[l-1][i][j] != 0) ^ user.cpp:73:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int l=0;l<m;l++) { ^