Compilare: user.cpp: In function ‘void calc(int, int)’: user.cpp:23:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] if (last[curr[j]][i] != -1) ^ user.cpp:24:38: warning: array subscript has type ‘char’ [-Wchar-subscripts] prec[i][j] = last[curr[j]][i]; ^ user.cpp:30:27: warning: array subscript has type ‘char’ [-Wchar-subscripts] calc (last[curr[j]][i] - 1, j - 1); ^ user.cpp:31:39: warning: array subscript has type ‘char’ [-Wchar-subscripts] prec[i][j] = prec[last[curr[j]][i] - 1][j - 1]; ^ user.cpp: In function ‘int main()’: user.cpp:50:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] last[sir[i]][i] = i; ^ user.cpp:37:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("mesaj2.in", "r", stdin); ^ user.cpp:38:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("mesaj2.out", "w", stdout); ^ user.cpp:40:15: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets (sir + 1); ^ user.cpp:57:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d\n", &N); ^ user.cpp:62:20: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets (curr + 1); ^ /tmp/ccOBiDJR.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.