UVa 10921 Find the Telephone Solution

#include<stdio.h>
#include<string.h>

int main()
{
char c[40];
int i,a;
    while(scanf("%s",&c)==1)
    {
        a=strlen(c);
        for(i=0;i<a;i++)
        {
            switch(c[i])
            {   
                 case 'A': {printf("2");break;}
                 case 'B': {printf("2");break;}
                 case 'C': {printf("2");break;}
                 case 'D': {printf("3");break;}
                 case 'E': {printf("3");break;}
                 case 'F': {printf("3");break;}
                 case 'G': {printf("4");break;}
                 case 'H': {printf("4");break;}
                 case 'I': {printf("4");break;}
                 case 'J': {printf("5");break;}
                 case 'K': {printf("5");break;}
                 case 'L': {printf("5");break;}
                 case 'M': {printf("6");break;}
                 case 'N': {printf("6");break;}
                 case 'O': {printf("6");break;}
                 case 'P': {printf("7");break;}
                 case 'Q': {printf("7");break;}
                 case 'R': {printf("7");break;}
                 case 'S': {printf("7");break;}
                 case 'T': {printf("8");break;}
                 case 'U': {printf("8");break;}
                 case 'V': {printf("8");break;}
                 case 'W': {printf("9");break;}
                 case 'X': {printf("9");break;}
                 case 'Y': {printf("9");break;}
                 case 'Z': {printf("9"); break;}
                 default: {printf("%c",c[i]);break;}
            }          
        }
        printf("\n");
    }
    return 0;
}