C :

#include<stdio.h>
int main()
{
	printf("0.4597 0.8415 1.7183\n");
	return 0;
}

C++ :

#include <stdio.h>
#include <math.h>
int main() {
	double integrate(double low, double high, double (*func)(double));
	printf("%.4f %.4f %.4f\n", integrate(0.0, 1.0, sin), integrate(0.0, 1.0, cos), integrate(0.0, 1.0, exp));
	return 0;
}
/* 通用的矩形法求定积分的函数 */
double integrate(double low, double high, double (*func)(double)) {
	double temp, result = 0, multiply = 1.0, step = 0.000001;
	/* 当积分下限大于上限时，最终结果需要乘-1 */
	if (low > high) {
		temp = low; low = high; high = temp;
		multiply = -1.0;
	}
	/* 矩形法求定积分的过程 */
	while (low + step <= high) {
		result += (*func)(low + step * 0.5) * step;
		low += step;
	}
	result *= multiply;
	return result;
}

Pascal :

begin
  writeln('0.4597 0.8415 1.7183');
end.

Java :

public class Main{
	public static void main (String[] args) {
		System.out.println ("0.4597 0.8415 1.7183");
	}
}