IT公司面试手册

void Multiple(char A[], char B[], char C[]) {

    int TMP, In=0, LenA=-1, LenB=-1;

    while(A[++LenA] != ‘\0′);

    while(B[++LenB] != ‘\0′);

    int Index, Start = LenA + LenB – 1;

    for(int i=LenB-1; i>=0; i–) {

        Index = Start–;

        if(B[i] != ’0′) {

            for(int In=0, j=LenA-1; j>=0; j–) {

                TMP = (C[Index]-’0′) + (A[j]-’0′) * (B[i] – ’0′) + In;

                C[Index--] = TMP % 10 + ’0′;

                In = TMP / 10;

            }

            C[Index] = In + ’0′;

        }

    }

}

int main(int argc, char* argv[]) {

    char A[] = “21839244444444448880088888889″;

    char B[] = “38888888888899999999999999988″;

char C[sizeof(A) + sizeof(B) - 1];

    for(int k=0; k<sizeof(C); k++)

        C[k] = ’0′;

    C[sizeof(C)-1] = ‘\0′;

    Multiple(A, B, C);

    for(int i=0; C[i] != ‘\0′; i++)

        printf(“%c”, C[i]);

}