Compilare: user.cpp: In function ‘int getdif(int, int, int, int)’: user.cpp:84:9: warning: unused variable ‘diff’ [-Wunused-variable] int diff[] = {a, b, c, d}; ^ user.cpp: In function ‘int main()’: user.cpp:116:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(unsigned int i = 2;i <= N - 2;i++) ^ user.cpp:117:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(unsigned int j = i + 1;j <= N - 1;j++) ^ user.cpp:118:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(unsigned int k = j + 1;k <= N;k++) { ^ user.cpp:119:37: warning: narrowing conversion of ‘i’ from ‘unsigned int’ to ‘int’ inside { } [-Wnarrowing] int nr1[] = {i, j, k}; ^ user.cpp:119:37: warning: narrowing conversion of ‘j’ from ‘unsigned int’ to ‘int’ inside { } [-Wnarrowing] user.cpp:119:37: warning: narrowing conversion of ‘k’ from ‘unsigned int’ to ‘int’ inside { } [-Wnarrowing] user.cpp: In function ‘char next()’: user.cpp:17:41: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf, 1, BUF, fin), pos = 0; ^