... <string.h> void main (){ int a[256]={0},i=0,max=0; char s [100 ]; cout<<"Nhap vao Xau : "; cin.getline(s ,100 ); while(s[i]!='\0')a[s[i++]]++; for(i=0;i<256;i++) ... <iostream.h> #include <string.h> void main (){ char s [100 ]; cout<<"Nhap Xau :"; cin.getline(s ,100 ); int i=0,b,c,d=0,e,k; do{ while(s[i]==' '&&s[i]!='\0')i++; ... nhiêu ký t #include<iostream.h> #include <string.h> void main (){ char s [100 ],d [100 ]; int dau,cuoi,i,j=0,t=0; ...