HDU 4811 Ball(思維)
阿新 • • 發佈:2018-12-13
題解:
先放頭和尾依次左右開始塞滿,找規律。
#include <algorithm> #include <iostream> #include <cstdlib> #include <cstring> #include <cstdio> #include <string> #include <vector> #include <bitset> #include <stack> #include <cmath> #include <deque> #include <queue> #include <list> #include <set> #include <map> #define line printf("---------------------------\n") #define mem(a, b) memset(a, b, sizeof(a)) #define pi acos(-1) using namespace std; typedef long long ll; const int inf = 0x3f3f3f3f; const int mod = 1e9+7; const int maxn = 2000+10; int main(){ ll a, b, c; while(~scanf("%d %d %d", &a, &b, &c)){ ll ans = 0; ll cnt = 0; if(a >= 2){ cnt += 2; }else{ cnt += a; } if(b >= 2){ cnt += 2; }else{ cnt += b; } if(c >= 2){ cnt += 2; }else{ cnt += c; } ans += (a+b+c-cnt)*cnt; ans += cnt*(cnt-1)/2; printf("%lld\n", ans); } }