#include <stdio.h>
 
int rangeSum(int a, int b) {
  int r;
  if (a == b) {
    printf("\n");
    return a;
  } else {
    printf("そのために、%d..%dの和 + %d を計算します ", a, b - 1, b);
    r = rangeSum(a, b - 1) + b;
  }
  return r;
}
 
int main(void) {
  int m, n;
  printf("mとnを入力: ");
  fflush(stdout);
  scanf("%d", &m);
  scanf("%d", &n); printf("%d..%dの和を計算します\n", m, n); printf("答えは%dです\n", rangeSum(m, n));
  return 0;
}
 

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MyA3

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