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#include <stdio.h>
int main(void) { int i, j, x, y, z; do { puts("please input an integer."); printf("x = "); scanf("%d", &x); } while (x < 0 || x > 100); putchar('\n'); y = x; z = x; while ( y >= 0) { printf("y:%d z:%d\n", y--, z++); } printf("\nsquare is %d.\n", x); printf("the propable sides i are :\n"); for (i = 1; i <= x; i ++) { if (i * i > x) break; if (x % i != 0) continue; printf("side1:%d side2:%d\n", i, x / i); } printf("\ndraw a star tangle!\n"); for (i = 1; i <= 3; i ++) { for (j = 1; j <= 5; j++) { putchar('*'); } putchar('\n'); } return 0; }