Compilare: user.cpp: In function ‘void CountingSort(u32*, u32*, u32)’: user.cpp:16:73: warning: operation on ‘i’ may be undefined [-Wsequence-point] for(u32 i = 0x0; i != 0x100; index[++i] = index[~-i] + frequence[~-i]); ^ user.cpp:16:73: warning: operation on ‘i’ may be undefined [-Wsequence-point] user.cpp: In function ‘int main()’: user.cpp:48:56: warning: operation on ‘i’ may be undefined [-Wsequence-point] v[--i] = (u64(v[-~i]) * A + B) % 0x367C2DC9; ^ user.cpp:55:56: warning: operation on ‘i’ may be undefined [-Wsequence-point] v[--i] = (u64(v[-~i]) * A + B) % 0x7CE67EF6; ^ user.cpp:62:56: warning: operation on ‘i’ may be undefined [-Wsequence-point] v[--i] = (u64(v[-~i]) * A + B) % 0x6F6E4E7B; ^ user.cpp: At global scope: user.cpp:23:37: warning: always_inline function might not be inlinable [-Wattributes] __attribute__((always_inline)) void write(u32 x) ^ user.cpp:10:37: warning: always_inline function might not be inlinable [-Wattributes] __attribute__((always_inline)) void CountingSort(u32 A[], u32 B[], u32 digit) ^ user.cpp: In function ‘int main()’: user.cpp:38:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("radixsort.in", "r", stdin); ^ user.cpp:40:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d", &N, &A, &B, &C); ^ user.cpp: In function ‘void CountingSort(u32*, u32*, u32)’: user.cpp:16:5: warning: iteration 255u invokes undefined behavior [-Waggressive-loop-optimizations] for(u32 i = 0x0; i != 0x100; index[++i] = index[~-i] + frequence[~-i]); ^ user.cpp:16:24: note: containing loop for(u32 i = 0x0; i != 0x100; index[++i] = index[~-i] + frequence[~-i]); ^