#include <stdio.h>
int main(void) {
int i, j, k, cnt = 0, ans;
for(i = 1; i < 200; i++) {
for(j = i, k = 0; j; j /= 10) k += j % 10;
if(k == 7) ans = i, cnt++; }
printf("最大：%d 合計：%d個\n", ans * 10 + 9, cnt);
return 0; }

#include <stdio.h>
int main(void) {
int a, b, c;
for(a = 1; a < 13; a++) {
for(b = 1; ; b++) {
c = 13 - a * b;
if(c <= 0) break;
if(a + b * c == 23) printf("a = %d b = %d c = %d\n", a, b, c); }}
return 0; }