字符串处理
#include<iostream> #include<algorithm> #include<cstdio> #include<cstdlib> #include<queue> #include<vector> #include<cstring> #include<cmath> #include<map> using namespace std; typedef long long ll; #define N 2011111 char str[1111]; int s[1111],f[1111][4],d[1111],b[1111]; int main() { int t,k; cin>>t; while(t--){ cin>>str>>k; int len=strlen(str); for(int i=0;i<len;i++){ if(str[i]=='A')s[i]=0; if(str[i]=='T')s[i]=1; if(str[i]=='C')s[i]=2; if(str[i]=='G')s[i]=3; d[i]=i; } int x=len-k; memset(f,0,sizeof(f)); memset(b,0,sizeof(b)); for(int i=0;i<k;i++){ d[i]=min(d[i],d[x+i]); d[i+x]=d[i]; if(!b[i])f[d[i]][s[i]]++;b[i]=1; if(!b[i+x])f[d[i]][s[i+x]]++;b[i+x]=1; } int ans=0; for(int i=0;i<k;i++){ x=0; int y=0; for(int j=0;j<4;j++){x+=f[i][j];y=max(y,f[i][j]);} ans+=x-y; } cout<<ans<<endl; } return 0; }