multiplication table using c

1#include <stdio.h>
2
3int main(){
4	//declaring variables
5    int n,i,a,start,end;
6    //taking and printing the instructions
7    printf("Enter first number from where you want to start multiplication : \n");
8    scanf("%d",&start);
9     printf("Enter Last number from where you want to end multiplication : \n");
10    scanf("%d",&end);
11  	//using loops
12
13    for(n=start;n<=end;n++){
14        a=0;
15        for(i=1;i<=10;i++){
16            a+=n; //setting the value of a. i used addition instead of multiplication
17          //because computer takes too much time for multiplating numbers than doing addition
18          
19            printf("%d x %d = %d\n",n,i,a);
20
21        }
22        printf("Multiplication has ended of %d\n\n",n);
23    }
24
25
26    return 0;
27
28
29}
30

1#include <stdio.h>
2int main(){
3    int a, b, c, e;
4    printf("Enter table format: \n");
5    scanf("%d", &a);
6    printf("Enter end of table: \n");
7    scanf("%d", &e);
8    for(b = 0; b <= e; b++){
9        printf("%d * % d = %d\n", b, a, a*b);
10    }
11}

1        printf(" %d x %d = %d \n ", number, i, number * i);

1#include <stdio.h>
2int main()
3{
4    // declaring table
5    int table[10][10];
6
7
8    int sum = 0;
9    // loop
10    for(int i = 0; i < 10; i++){
11        printf("%d table starting \n\n",i + 1);
12        for(int j = 0; j < 10; j++){
13             // using addition instead of multiply for better performance
14            sum += (i + 1);
15            //
16            table[i][j] = sum;
17            // printing table
18            printf("%d x %d = %d \n",i + 1,j + 1,table[i][j]);
19        }
20        sum = 0;
21        printf("\n");
22    }
23
24}