UVA 12545 Bits Equalizer
#include<bits/stdc++.h> #define REP(i,a,b) for(int i=a;i<=b;i++) #define MS0(a) memset(a,0,sizeof(a)) using namespace std; typedef long long ll; const int maxn=1000100; const int INF=1<<29; char s[maxn],t[maxn]; int len; int c10,c01,c1,c0; int main() { freopen("in.txt","r",stdin); int T;cin>>T; int casen=1; while(T--){ scanf("%s%s",s,t); len=strlen(s); c10=c01=c1=c0=0; REP(i,0,len-1){ if(s[i]=='0'&&t[i]=='1') c01++; if(s[i]=='1'&&t[i]=='0') c10++; if(s[i]=='?'&&t[i]=='0') c0++; if(s[i]=='?'&&t[i]=='1') c1++; } //cout<<c01<<" "<<c10<<" "<<c0<<" "<<c1<<endl; int ans=0; if(c01>=c10){ ans+=c10; c01-=c10; ans+=c01+c1+c0; } else{ ans+=c01; c10-=c01; if(c1>=c10){ ans+=c10*2; c1-=c10; ans+=c1+c0; } else ans=-1; } printf("Case %d: %d\n",casen++,ans); } return 0; }
贪心,分类讨论一下确定一下操作的优先顺序就好了。
没有AC不了的题,只有不努力的ACMER!