标签:style http color os io ar for 2014 cti
真郁闷,一道普通的搜索题 我拿dp的方法去做,结果一直TLE和WA
如果所有数的和为奇数,肯定没有正解。
14133454 | 10317 | Equating Equations | Accepted | C++ | 0.102 | 2014-09-02 09:01:23 |
#include <iostream> #include <cstdlib> #include <cstdio> #include <string> #include <cstring> #include <cmath> #include <vector> #include <queue> #include <set> #include <map> #include <stack> #include <algorithm> using namespace std; const double eps = 1e-10; #define MAXD 110 #define _PI acos(-1.0) int array[MAXD]; int _ansx[MAXD],_ansy[MAXD]; int _x , _y; int size , add ; int aim; int vis[MAXD]; int _operator[MAXD]; bool dfs(int ans,int cur,int pos){ if(cur == add){ if(ans == aim) return true; else return false; } for(int i = pos ; i < size ; i++)if(!vis[i]){ vis[i] = 1; if(ans + array[i] <= aim && dfs(ans + array[i],cur + 1,i + 1)) return true; vis[i] = 0; } return false; } void init(){ for(int i = 0 ; i < size ; i++){ if(vis[i]){ _ansx[_x ++] = array[i]; } else{ _ansy[_y ++] = array[i]; } } } int main(){ char oper[MAXD]; char m; while(scanf("%d",&array[0]) != EOF){ _operator[0] = 1; memset(vis,0,sizeof(vis)); size = 1; _x = 0 ; _y = 0; add = 1; int p = 0; int pos ,sum = array[0]; while((m = getchar())){ if(m == '\n') break; scanf("%s",oper); if(oper[0] == '+'){ if(!p){ add ++; _operator[size] = 1; } else{ _operator[size] = -1; } } if(oper[0] == '-'){ if(!p){ _operator[size] = -1; } else{ _operator[size] = 1; add++; } } if(oper[0] == '='){ p = 1; pos = size; _operator[size] = -1; } scanf("%d",&array[size++]); sum += array[size - 1]; } p = 0; aim = sum / 2; if(sum % 2 == 0 && dfs(0,0,0)){ init(); for(int i = 0 , p1 = 0 , q1 = 0 ; i < size ; i++){ if(i == 0) printf("%d",_ansx[p1++]); else if(i == pos){ p = 1; printf(" = %d",_ansy[q1++]); } else if(_operator[i] == 1){ if(!p) printf(" + %d",_ansx[p1++]); else printf(" - %d",_ansx[p1++]); } else if(_operator[i] == -1){ if(!p) printf(" - %d",_ansy[q1++]); else printf(" + %d",_ansy[q1++]); } } printf("\n"); } else printf("no solution\n"); } return 0; }
【UVA】10317 - Equating Equations(dfs + 剪枝)
标签:style http color os io ar for 2014 cti
原文地址:http://blog.csdn.net/u013451221/article/details/39008709