self learn c language

Display asterisk from one to nine. Add one thing

#include <stdio.h>

int main(void){

  int n = 0;
  for(n;n<10;n++){
    int i = 0;
    for(i;i<=n;i++){
      printf("*");
    }
    printf("\n");
  }

  return 0;
}

Addition from one to one hundred.

#include <stdio.h>

int main(void){

  int wa = 0;
  int i = 1;
  while(i<=100){
    wa = wa+i;
    i++;
  }
  printf("%d\n",wa);

  return 0;
}

If input value is not 0,Ask repeat "please input something" and to add input value.

#include <stdio.h>

int main(void){
  int wa = 0;
  int data;
  printf("いれて\n");
  scanf("%d",&data);
  while(data!=0){
    wa=wa+data;
    printf("%d",wa);
    printf("いれて\n");
    scanf("%d",&data);
  }

  return 0;
}