Roman2Int

int romanToInt(char * s){
    int count = 0;
    while (*s) {
        switch(*s) {
        case 'I':
            if (*(s+1) == 'V' || *(s+1) == 'X') count -= 1;
            else count += 1;
            break;
        case 'X':
            if (*(s+1) == 'L' || *(s+1) == 'C') count -= 10;
            else count += 10;
            break;
        case 'C':
            if (*(s+1) == 'D' || *(s+1) == 'M') count -= 100;
            else count += 100;
            break;
        case 'V':
            count += 5;
            break;
        case 'L':
            count += 50;
            break;
        case 'D':
            count += 500;
            break;
        case 'M':
            count += 1000;
            break;
        default:
            break;
        }
        ++s;
    }
    return count;
}