Paths through the Hourglass UVA10564

#include <iostream>#include <cstdio>#include <cstdlib>#include <cmath>#include <queue>#include <algorithm>#include <vector>#include <cstring>#include <stack>#include <cctype>#include <utility>   #include <map>#include <string>  #include <climits> #include <set>#include <string> #include <sstream>#include <utility>#include <ctime> using std::priority_queue;using std::vector;using std::swap;using std::stack;using std::sort;using std::max;using std::min;using std::pair;using std::map;using std::string;using std::cin;using std::cout;using std::set;using std::queue;using std::string;using std::istringstream;using std::make_pair;using std::greater;using std::endl;vector<int> st[45][25];long long vis[45][25][501];int arr[45][25];int main(){int n, S;while(scanf("%d%d", &n, &S), n || S){int tn = n*2;memset(vis+1, 0, sizeof(vis[1])*tn);for(int i = 1; i <= n; ++i){int lim = n-i+1;for(int j = 1; j <= lim; ++j){scanf("%d", arr[i]+j);st[i][j].clear();}}for(int i = n+1; i < tn; ++i){int lim = i-n+1;for(int j = 1; j <= lim; ++j){scanf("%d", arr[i]+j);st[i][j].clear();}}for(int i = 1; i <= n; ++i)if(arr[tn-1][i] <= S){++vis[tn-1][i][arr[tn-1][i]];st[tn-1][i].push_back(arr[tn-1][i]);}for(int i = tn-2; i >= n; --i){int lim = i-n+1;int ti = i+1;for(int j = 1; j <= lim; ++j){int ts = st[ti][j].size();for(int k = 0; k < ts; ++k){int temp = st[ti][j][k];int t2 = temp+arr[i][j];if(t2 <= S){if(!vis[i][j][t2])st[i][j].push_back(t2);vis[i][j][t2] += vis[ti][j][temp];}}int tj = j+1;ts = st[ti][tj].size();for(int k = 0; k < ts; ++k){int temp = st[ti][tj][k];int t2 = temp+arr[i][j];if(t2 <= S){if(!vis[i][j][t2])st[i][j].push_back(t2);vis[i][j][t2] += vis[ti][tj][temp];}}}}for(int i = n; i > 1; --i){int lim = n-i+1;for(int j = 1; j <= lim; ++j){int ts = st[i][j].size();for(int k = 0; k < ts; ++k){int t1 = st[i][j][k];int t2 = t1+arr[i-1][j];if(t2 <= S){if(!vis[i-1][j][t2])st[i-1][j].push_back(t2);vis[i-1][j][t2] += vis[i][j][t1];}t2 = t1+arr[i-1][j+1];if(t2 <= S){if(!vis[i-1][j+1][t2])st[i-1][j+1].push_back(t2);vis[i-1][j+1][t2] += vis[i][j][t1];}}}}long long ans = 0LL;int s;for(int i = n; i >= 1; --i)if(vis[1][i][S]){s = i;ans += vis[1][i][S];}printf("%lld\n", ans);if(ans){printf("%d ", s-1);int temp = S;for(int i = 1; i < n; ++i){temp -= arr[i][s];if(s == 1){putchar('R');continue;}if(s == n-i+1){putchar('L');--s;continue;}if(vis[i+1][s-1][temp]){putchar('L');--s;}else{putchar('R');}}for(int i = n; i < tn-1; ++i){temp -= arr[i][s];if(vis[i+1][s][temp]){putchar('L');}else{putchar('R');++s;}}putchar('\n');}elseputchar('\n');}return 0;}