Compilare: main.cpp: In function 'int main()': main.cpp:77:28: warning: statement has no effect [-Wunused-value] a[i][j]==0; ~~~~~~~^~~ main.cpp:98:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation] for(i=1; i<=n; i++) ^~~ main.cpp:111:13: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for' if(nr==nr1) ^~