#include<bits/stdc++.h> #include "message.h" #include "futbol.h" using namespace std; long long int n,k,p,i,w,h,f[10000007]; long long int pow(long long int base, long long int exp) { long long int res=1; while(exp > 0) { if(exp%2 == 1) { res*=base; res%=p; } base*=base; base%=p; exp/=2; } return res; } int main() { if(MyNodeId() > 0) { return 0; } f[0]=1; // scanf("%lld%lld%lld", &n, &k, &p); n=GetN(); k=GetK(); p=GetP(); for(i=1; i<=n; i++) { f[i]=f[i-1]*i; f[i]%=p; // printf("TEST factorial[%lld]=%lld;\n", i, f[i]); } for(i=0; i<=k; i++) { h=f[n]; h*=pow((f[i]*f[n-i])%p, p-2); w+=h; w%=p; } printf("%lld", w); return 0; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 | #include<bits/stdc++.h> #include "message.h" #include "futbol.h" using namespace std; long long int n,k,p,i,w,h,f[10000007]; long long int pow(long long int base, long long int exp) { long long int res=1; while(exp > 0) { if(exp%2 == 1) { res*=base; res%=p; } base*=base; base%=p; exp/=2; } return res; } int main() { if(MyNodeId() > 0) { return 0; } f[0]=1; // scanf("%lld%lld%lld", &n, &k, &p); n=GetN(); k=GetK(); p=GetP(); for(i=1; i<=n; i++) { f[i]=f[i-1]*i; f[i]%=p; // printf("TEST factorial[%lld]=%lld;\n", i, f[i]); } for(i=0; i<=k; i++) { h=f[n]; h*=pow((f[i]*f[n-i])%p, p-2); w+=h; w%=p; } printf("%lld", w); return 0; } |