Compilare: main.cpp: In function 'int main()': main.cpp:92:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0 ; j < v[i].size() ; j++){ ~~^~~~~~~~~~~~~ main.cpp:12:25: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&t); ^ main.cpp:14:29: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&n); ^ main.cpp:20:43: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&a[i][j]); ^ main.cpp:30:25: warning: 'n2' may be used uninitialized in this function [-Wmaybe-uninitialized] h.push(make_pair(a[n1][n2] , make_pair(n1 , n2))); ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:11:25: warning: 'n1' may be used uninitialized in this function [-Wmaybe-uninitialized] int t , n , i , j , n1 , n2 , vall , mch , maxi; ^~