Compilare: main.cpp: In function 'int main()': main.cpp:69:35: warning: array subscript has type 'char' [-Wchar-subscripts] if (!merg[a[i][y1]]) ^ main.cpp:71:34: warning: array subscript has type 'char' [-Wchar-subscripts] merg[a[i][y1]] = 1; ^ main.cpp:80:35: warning: array subscript has type 'char' [-Wchar-subscripts] if (!merg[a[i][y2]]) ^ main.cpp:82:34: warning: array subscript has type 'char' [-Wchar-subscripts] merg[a[i][y2]] = 1; ^ main.cpp:91:35: warning: array subscript has type 'char' [-Wchar-subscripts] if (!merg[a[x1][j]]) ^ main.cpp:93:34: warning: array subscript has type 'char' [-Wchar-subscripts] merg[a[x1][j]] = 1; ^ main.cpp:102:35: warning: array subscript has type 'char' [-Wchar-subscripts] if (!merg[a[x2][j]]) ^ main.cpp:104:34: warning: array subscript has type 'char' [-Wchar-subscripts] merg[a[x2][j]] = 1; ^