update

CMakeLists.txt

@@ -4,7 +4,7 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 add_compile_options(-Wall)
 include_directories(${CMAKE_CURRENT_LIST_DIR}/include)
 
-set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 

src/2/P1223.cpp

@@ -0,0 +1,29 @@
+#include <algorithm>
+#include <cstdint>
+#include <cstdlib>
+#include <iomanip>
+#include <ios>
+#include <iostream>
+#include <ostream>
+#include <utility>
+#include <vector>
+
+
+int main(){
+    using ll = int64_t;
+    ll n,nowWait=0,sumWait=0;
+    std::cin>>n;
+    std::vector<std::pair<ll, ll>> a(n+1);
+    for(ll i=1;i<=n;i++){
+        std::cin>>a[i].first;
+        a[i].second=i;
+    }
+    std::sort(a.begin()+1,a.end());
+    for(ll i=1;i<=n;i++){
+        sumWait+=nowWait;
+        std::cout<<a[i].second<<" ";
+        nowWait+=a[i].first;
+    }
+    std::cout<<std::fixed<<std::setprecision(2)<<'\n'<<(double(sumWait)/double(n))<<'\n'<<std::flush;
+    quick_exit(0);
+}

src/2/P1375.cpp

@@ -0,0 +1,38 @@
+#include <cstdint>
+#include <iostream>
+
+using ll = int64_t;
+
+constexpr ll p=1e9+7;
+const ll n=[]()->ll{ll n;std::cin>>n;return n;}();
+
+ll qpow(ll b,ll e){
+    ll r{1};
+    while(e){
+        if(e&1)r=r*b%p;
+        b=b*b%p;
+        e/=2;
+    }
+    return r;
+}
+
+ll inv(ll n){
+    return qpow(n, p-2);
+}
+
+ll mfact(const ll&b){
+    ll r{1};
+    for(ll i{1};i<=b;i++){
+        r=r*i%p;
+    }
+    return r;
+}
+
+ll C(const ll &n,const ll &m){
+    return mfact(n)*inv(mfact(m))%p*inv(mfact(n-m))%p;
+}
+
+int main(){
+    const ll ans = C(2*n,n)-C(2*n,n-1);
+    std::cout<<(ans%p+p)%p<<'\n';
+}

src/2/P5656.cpp

@@ -1,20 +1,42 @@
+#include <algorithm>
 #include <cstdint>
+#include <iostream>
+#include <tuple>
 
 using ll = int64_t;
+
 ll T;
 
-ll exgcd(ll a,ll b,ll&x,ll&y){
+std::tuple<ll,ll,ll> exgcd(ll const&a,ll const& b){
     if(b==0){
-        x=1,y=0;
-        return a;
+        return std::make_tuple(a,1,0);
     }
-    ll d = exgcd(b,a%b,x,y);
-    ll tempy = y;
+    auto [d,x,y] = exgcd(b, a%b);
+    ll oldy{y};
     y=x-a/b*y;
-    x=tempy;
-    return d;
+    x=oldy;
+    return std::make_tuple(d,x,y);
+}
+
+ll divup(ll const&a,ll const&b){
+    return (a+(b>0?b-1:b+1))/b;
 }
 
 int main(){
-    
+    std::cin>>T;
+    while(T--){
+        const auto [a,b,c] {[]()->std::tuple<ll,ll,ll>{ll a,b,c;std::cin>>a>>b>>c;return std::make_tuple(a,b,c);}()};
+        const auto [d,x1,y1] {exgcd(a,b)};
+        if(c%d!=0){
+            std::cout<<"-1\n";
+            continue;
+        }
+        const ll kmin{divup(-x1*d,b)},kmax{y1*d/a};
+        const ll knum{std::max(ll(0),kmax-kmin+1)};
+        if(knum==0){
+            std::cout<<(x1+kmax*b/d)<<' '<<(y1-kmin*a/d)<<'\n';
+        }else{
+            std::cout<<(x1+kmin*b/d)<<' '<<(y1-kmax*a/d)<<(x1+kmax*b/d)<<' '<<(y1-kmin*a/d)<<'\n';
+        }
+    }
 }