Good Vegetable 4级算法题 分值: [320/3120] 问题: [8/78]

#include <cstdio>
#include <cstring>
#include <cmath>
#include <queue>
#include <vector>
#include <string>
#include <stack>
#include <set>
#include <map>
#include <iostream>
#include <algorithm>
using namespace std;
#define MP make_pair
#define PB push_back
typedef long long LL;
typedef pair<int,int> Pii;
const int inf = 0x3f3f3f3f;
const LL INF = 1LL<<60;
const int mod = 1000000007;
const int N = 1e5+5;
const double Pi = acos(-1.0);
const int maxn = 1e5+5;
int a , b , c;
int l ;
LL res = 0;
LL solve(int bigest , int x, int y){
    LL ans = 0;
    int _t = bigest + x + y + l;
    for(int i = 0 ; i <= l ; i++){
        int t = min(_t -  bigest - i , bigest + i);
        if(x + y <= t){
            ans += 1LL * (t - x - y + 2) * (t - x - y + 1) / 2;
        }
    }
    return ans ;
}
void work() {
    cin>>a>>b>>c>>l;
    res = 1LL * (l + 3) * (l + 2) * (l + 1) / 6;
    res -= solve(a,b,c);
    res -= solve(b,a,c);
    res -= solve(c,a,b);
    cout<<res<<endl;
}
int main() {
#ifdef local
    freopen("in", "r", stdin);
#endif
    work();
}

#include <cstdio>
#include <cstring>
#include <cmath>
#include <queue>
#include <vector>
#include <string>
#include <stack>
#include <set>
#include <map>
#include <iostream>
#include <algorithm>
using namespace std;
#define MP make_pair
#define PB push_back
typedef long long LL;
typedef pair<int,int> Pii;
const int inf = 0x3f3f3f3f;
const LL INF = 1LL<<60;
const int mod = 1000000007;
const int N = 1e5+5;
const double Pi = acos(-1.0);
const int maxn = 1e5+5;
LL ztt = 285;//1^2 + 2^2 + 3^2……+9^2
LL tp[25];
LL sum[25];
LL cnt[25];//有前导0
LL all[25];//无前导0
int base[65];
int len = 0;
void add(LL &a,LL b) {
    a += b;
    if(a >= mod)a -= mod;
}
LL dfs(int cur) {
    LL res = 0;
    if(!cur) {
        for(int i = len; i; i--) {
            add(res,base[i]*base[len-i+1]);
        }
        return res;
    }
    for(int i = (cur==len); i < base[cur]; i++) {
        for(int j = len ; j; j--) {
            int k = len - j + 1;
            if(j > cur) {
                if(k > cur)add(res,(base[j] * base[k] * tp[cur-1]) % mod);
                else if(k == cur)add(res,(base[j] * i * tp[cur-1]) % mod);
                else add(res,(base[j] * 45 * tp[cur-2]) % mod);
            }
            else if(j == cur){
                if(k > cur)add(res,(base[k] * i * tp[cur-1]) % mod);
                else if(k == cur)add(res,(i * i * tp[cur-1]) % mod);
                else add(res,(i * 45 * tp[cur-2]) % mod);
            }
            else {
                if(k > cur)add(res,(base[k] * 45 * tp[cur-2]) % mod);
                else if(k == cur)add(res,(i * 45 * tp[cur-2]) % mod);
                else {
                    if(j == k)add(res,(ztt * tp[cur-2]) % mod);
                    else add(res,(45 * 45 * tp[cur-3]) % mod);
                }
            }
        }
    }
    return (res + dfs(cur - 1)) % mod;
}
LL solve(LL x) {
    if(x < 0)return 0;
    len = 0;
    for(; x; x/=10) {
        base[++len] = x%10;
    }
    return (dfs(len) + sum[len-1]) % mod;
}
void work() {
    LL r,l;
    cin>>l>>r;
    cout<<(solve(r) - solve(l-1) + mod) % mod<<endl;
}
void init() {
    cnt[0] = all[0] = 0;
    cnt[1] = all[1] = ztt;
    tp[0] = 1;
    tp[1] = 10;
    for(int i = 2; i < 19; i++) {
        tp[i] = (tp[i-1] * 10) % mod;
        all[i] = ((cnt[i-2] * 9 * 10)%mod + (45 * 45 * 2 * tp[i-2]) % mod) % mod;
        cnt[i] = ((cnt[i-2] * 10 * 10)%mod + (45 * 45 * 2 * tp[i-2]) % mod) % mod;
    }
    for(int i = 1; i < 19; i++) {
        sum[i] = (sum[i-1] + all[i]) % mod;
    }
}
int main() {
#ifdef local
    freopen("in", "r", stdin);
#endif
    init();
    work();
}

#include <cstdio>
#include <cstring>
#include <cmath>
#include <queue>
#include <vector>
#include <string>
#include <stack>
#include <set>
#include <map>
#include <iostream>
#include <algorithm>
using namespace std;
#define MP make_pair
#define PB push_back
typedef long long LL;
typedef pair<int,int> Pii;
const int inf = 0x3f3f3f3f;
const LL INF = 1LL<<60;
const int mod = 1000000007;
const int N = 1e5+5;
const double Pi = acos(-1.0);
const int maxn = 1e5+5;
char maz[505][505];
LL dp[2][505][505];
int n , m;
void update(LL &a,LL b) {
    a += b;
    if(a >= mod)a -= mod;
}
void work() {
    int s = 0;
    int half = (n + m) >> 1;
    dp[s][1][n] = (maz[1][1] == maz[n][m]);
    for(int i = 2 ; i <= half; i++) {
        s^=1;
        memset(dp[s],0,sizeof(dp[s]));
        for(int x = 1 ; x <= n && x <= i; x++) {
            for(int _x = n; _x > 0 && _x >= n - i + 1 ; _x--) {
                int y = i - x + 1;
                int _y = m + n + 1 - i - _x;
                if(maz[x][y]!=maz[_x][_y])continue;
//                cout<<"-----"<<endl;
//                cout<<i<<endl;
//                cout<<x<<" "<<y<<endl;
//                cout<<_x<<" "<<_y<<endl;
//                cout<<"-----"<<endl;
                update(dp[s][x][_x],dp[s^1][x][_x]);
                update(dp[s][x][_x],dp[s^1][x-1][_x]);
                update(dp[s][x][_x],dp[s^1][x-1][_x+1]);
                update(dp[s][x][_x],dp[s^1][x][_x+1]);
            }
        }
    }
    LL res = 0;
    if((n+m+1) & 1) {
        for(int x = 1; x <= n; x++) {
            for(int _x = n ; _x ; _x--) {
                int y = half - x + 1;
                int _y = m + n + 1 - half - _x;
                if(x==_x&&y==_y)
                    update(res,dp[s][x][_x]);
            }
        }
    } else {
        for(int x = 1; x <= n; x++) {
            for(int _x = n ; _x ; _x--) {
                int y = half - x + 1;
                int _y = m + n + 1 - half - _x;
                if(x==_x||y==_y)
                    update(res,dp[s][x][_x]);
            }
        }
    }
    cout<<res<<endl;
}
void init() {
    cin>>n>>m;
    for(int i = 1; i <= n; i++)scanf("%s",maz[i]+1);
}
int main() {
#ifdef local
    freopen("in", "r", stdin);
#endif
    init();
    work();
}