chase.cpp: In function 'void DFS(int)':
chase.cpp:5:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
#define REP(x, a, b) for (int x = a; x < b; ++x)
^
chase.cpp:23:5: note: in expansion of macro 'REP'
REP(k, 0, adj[u].size()) {
^
chase.cpp: In function 'int Compute(int, int)':
chase.cpp:5:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
#define REP(x, a, b) for (int x = a; x < b; ++x)
^
chase.cpp:35:9: note: in expansion of macro 'REP'
REP(k, 0, adj[t].size()) {
^
chase.cpp:5:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
#define REP(x, a, b) for (int x = a; x < b; ++x)
^
chase.cpp:43:5: note: in expansion of macro 'REP'
REP(k, 0, adj[s].size()) {
^
chase.cpp:32:9: warning: unused variable 's1' [-Wunused-variable]
int s1 = 0, s2 = 0;
^
chase.cpp: In function 'int main()':
chase.cpp:56:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d", &n, &m);
^
chase.cpp:57:36: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
FOR(i, 1, n) scanf("%d", &a[i]);
^
chase.cpp:59:40: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
int u, v; scanf("%d%d", &u, &v);
^