#include using namespace std; typedef signed long long ll; #undef _P #define _P(...) (void)printf(__VA_ARGS__) #define FOR(x,to) for(x=0;x<(to);x++) #define FORR(x,arr) for(auto& x:arr) #define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++) #define ALL(a) (a.begin()),(a.end()) #define ZERO(a) memset(a,0,sizeof(a)) #define MINUS(a) memset(a,0xff,sizeof(a)) //------------------------------------------------------- int A,B,C,D; void solve() { int i,j,k,l,r,x,y; string s; cin>>A>>B>>C>>D; int ret=0; for(i=A;i<=B;i++) { for(j=C;j<=D;j++) { ret+=i!=j; } } cout<