2012百度之星E题

#include"stdio.h"#include"string.h"#include"ctype.h"int main(){ int i,j,fla1=1,fla2=1; char a[141]; gets(a); int n=strlen(a); if(!islower(a[0]))  {   printf("Error!\n");         return 0;  }    for(i=0;i<n;i++) {  if(islower(a[i]))continue;  if(a[i]=='_'&&i+1<n&&islower(a[i+1]))  {fla1=0;i++;continue;}  if(isupper(a[i]))  {fla2=0;continue;}        fla1=0;fla2=0;  break; } if(fla1==0&&fla2==0)  {   printf("Error!\n");  return 0;  } if(fla1)  for(i=0;i<n;i++)  if(isupper(a[i]))  {

   for(j=n+1;j>i+1;j--)    a[j]=a[j-1];   a[j]=tolower(a[i]);   a[i]='_';   n++;  } if(fla2)  for(i=0;i<n;i++)  if(a[i]=='_'&&islower(a[i+1]))  {   n--;   a[i]=toupper(a[i+1]);   for(j=i+1;j<=n;j++)    a[j]=a[j+1];  }    puts(a);

  return 0;}